# Annual investment return

This is the yearly return you assume if you invest money instead of using it for the property.

Why it matters:
- It affects the rent-vs-buy comparison because money not spent on buying can be treated as invested in the model.
- It changes the value of the comparison baseline over time.

Example:
- If you want to test a `5%` return, enter `5`.
- A more cautious case might be `2%` to `3%`.

Important note:
- This is a user assumption, not guaranteed market performance.


Annual investment return

# Annual rent increase

This is the percentage by which comparable rent is expected to rise each year.

It is used when projecting the cost of renting over time.

Why it matters:
- It makes the rent comparison more realistic.
- It can shorten the time until buying becomes financially better than renting.
- It reflects inflation, demand, and local market pressure.

Example:
- If rents typically rise by `3%` per year, enter `3`.
- A monthly rent of `€1,800` would become about `€1,854` after one year at `3%` growth.

Important note:
- If you expect unusually high rent growth in your area, use a higher value.
- If rent is regulated or constrained, use a lower value.

What the law allows in Germany:
- For a normal rent increase under `BGB § 558`, the landlord may demand an increase only after the rent has remained unchanged for `15 months`.
- The demand may be made at the earliest `1 year` after the most recent rent increase.
- Within `3 years`, the rent may generally not rise by more than `20%` in total, or `15%` in some municipalities with a tightened cap.
- For indexed rent or stepped rent contracts, the pattern is different and increases can be tied to the contract terms rather than a simple annual percentage.

What this means in practice:
- There is no single official “average landlord raises rent every X months” number, because it depends on the lease type, local rules, and whether the landlord actually uses a permitted increase.
- For a standard lease, it is usually wrong to assume rent climbs every month.
- A yearly growth assumption in this calculator is just a projection tool for comparison, not a claim that the landlord literally increases rent every year.

Examples:
- Conservative projection: `1%` to `2%`
- Typical planning assumption: `2%` to `3%`
- Higher-growth scenario: `4%` or more

Source:
- German Civil Code (`BGB`), Sections `557`, `557a`, `557b`, and `558` via Gesetze im Internet.


Annual rent increase

# Annual special repayment

This is an optional extra principal repayment you make on top of the normal monthly mortgage payment.

It goes directly toward reducing the loan balance.

Why it matters:
- It can shorten the total loan term.
- It reduces future interest costs.
- It gives you flexibility if you receive a bonus or extra savings.

Example:
- If you enter `€5,000` per year, you make an extra principal payment of `€5,000` each year.
- On a large loan, that can save meaningful interest over time.

Important note:
- Some mortgage contracts limit the size of special repayments.
- Always check whether the bank allows this and whether there is a cap.


Annual special repayment

# Appreciation rate

This is the expected annual increase in the property's value.

It represents how much the property may be worth in the future if market conditions improve.

Why it matters:
- It affects equity growth over time.
- It changes the estimated break-even point.
- It can materially affect the long-term outcome of buying versus renting.

Example:
- If you expect the home to rise by `2.5%` per year, enter `2.5`.
- A `€500,000` home growing at `2.5%` annually would be worth about `€512,500` after one year, before other market effects.
- If you want a conservative long-term assumption, something around `1%` to `3%` can be a reasonable starting range.
- If you want to reflect the strong growth seen in parts of the last decade, you could test a higher scenario closer to `5%` or `6%`.

Recent Germany house-price trend examples from Destatis:
- `2019 Q2`: `+5.2%` year on year
- `2019 Q4`: `+5.7%` year on year
- `2020 Q1`: `+6.8%` year on year
- `2020 Q3`: `+7.8%` year on year
- `2021 Q3`: `+12.0%` year on year
- `2022 Q3`: `+4.9%` year on year
- `2023 Q3`: `-10.2%` year on year
- `2024 Q3`: `-0.7%` year on year
- `2025`: `+3.2%` year on year

What that means in practice:
- A single fixed appreciation number is only a scenario.
- A realistic user may want to compare at least three cases:
  - conservative: `1%`
  - base case: `2.5%`
  - optimistic: `4%` to `6%`

Important note:
- This is an assumption, not a guarantee.
- In weak markets, the value may stay flat or even fall.

Source:
- German Federal Statistical Office (Destatis), Residential property price indices and press releases, accessed June 2026.


Appreciation rate

# Break-even

This is the estimated point where the buy and rent scenarios become equal in the model.

Why it matters:
- It gives you a rough time horizon for when buying may stop being worse than renting.
- It helps you compare short-term and long-term outcomes.

Example:
- A break-even point of `7.5 years` means the model thinks the buy scenario catches up around that time.

Important note:
- Break-even depends on the assumptions you enter, especially rent growth, appreciation, interest rate, and holding period.


Break-even

# Bundesland

The `Bundesland` determines which German federal state rules should be used for state-specific purchase costs.

For this project, the main effect is the property transfer tax rate, which varies by state.

Why it matters:
- Different states charge different `Grunderwerbsteuer` rates.
- That rate can materially change your upfront cash requirement.
- It is one of the easiest costs to underestimate when buying property in Germany.

Example:
- If the property is in Berlin, the transfer tax is higher than in some other states.
- On a `€500,000` purchase, even a one percentage point difference changes the tax by `€5,000`.

Important note:
- The state selection should reflect where the property is located, not where the buyer lives.
- This field should always match the actual legal location of the property.


Bundesland

# Buying cost

This is the calculator’s estimate of the total cost of buying the property over the selected holding period.

Why it matters:
- It combines the upfront cash needed, mortgage payments, maintenance reserve, and the remaining mortgage balance effect at the end of the period.
- It gives you a single number to compare against renting.

Example:
- If the result is lower than renting, buying may be financially better in this model.

Important note:
- This is a model comparison, not a guaranteed real-world cost.


Buying cost

# Down payment

This is the amount of your own cash you put into the purchase instead of borrowing it.

It reduces the size of the loan and usually lowers the monthly payment and total interest cost.

Why it matters:
- A larger down payment means a smaller mortgage.
- It can improve your loan-to-value ratio.
- It often makes the financing more attractive to a bank.

Example:
- If the purchase price is `€500,000` and you contribute `€100,000`, the remaining `€400,000` is the loan amount before fees and taxes.
- If you have more cash available, you may be able to reduce interest costs significantly over the full term.

Important note:
- This is not the same as all upfront costs.
- In Germany, taxes and fees often need to be paid in addition to the down payment.


Down payment

# Fixed interest period

This is the number of years for which the bank guarantees the interest rate.

During this period, the agreed rate usually stays fixed even if market rates change.

Why it matters:
- A longer fixed period gives more payment certainty.
- A shorter fixed period may start with a better rate but exposes you to refinancing risk sooner.

Example:
- If you choose a fixed period of `10 years`, your rate stays unchanged for that period under the contract.
- If you choose `15` or `20 years`, you usually pay for more rate security.

Important note:
- The fixed period does not automatically mean the loan is fully repaid by then.
- At the end of the fixed period, the remaining balance is typically refinanced or renegotiated.


Fixed interest period

# Holding period

This is how long you plan to keep the property before you compare the outcome.

Why it matters:
- It sets the time window for the buy-vs-rent comparison.
- It affects how much mortgage you pay down, how much rent you would have paid instead, and how much the property may change in value.

Example:
- If you want to know the result after `10 years`, enter `10`.
- If you expect to sell after `5 years`, use `5` instead.

Important note:
- This is your chosen planning horizon, not a market fact.


Holding period

# Inflation rate

This is the yearly rate at which general prices are assumed to rise in the model.

Why it matters:
- It can influence how you think about future costs in real terms.
- It helps when comparing today's money with future money.

Example:
- If you want to use `2.6%`, enter `2.6`.
- If you want a more conservative assumption, try a lower number.

Important note:
- Inflation is a scenario input here, not a fixed fact for every future year.


Inflation rate

# Initial repayment rate

This is the starting principal repayment rate, expressed as a percentage of the loan amount per year.

In a standard German annuity mortgage, the monthly payment is usually built from two parts:
- interest
- repayment of principal

Why it matters:
- A higher repayment rate reduces the loan faster.
- A lower repayment rate keeps the monthly payment lower, but the debt lasts longer and interest costs rise.

Example:
- If the loan is `€400,000` and the initial repayment rate is `2%`, the first-year principal repayment target is roughly `€8,000`, before interest is added.
- With a higher repayment rate such as `3%`, you repay the debt faster and shorten the life of the loan.

Important note:
- This is not the same as the interest rate.
- If the repayment rate is too low, the loan can remain outstanding for a very long time.


Initial repayment rate

# Interest rate

This is the annual borrowing cost charged by the bank on the outstanding loan balance.

It is one of the most important inputs in a mortgage calculation.

Why it matters:
- A higher rate increases the monthly payment and total interest.
- A lower rate can make buying much more affordable over time.
- It affects how fast the loan balance falls.

Example:
- On a `€400,000` loan, an interest rate of `3.8%` means the bank charges interest on the remaining debt at that annual rate.
- Even a small change, such as from `3.8%` to `4.3%`, can noticeably change the monthly payment over many years.

Important note:
- The rate is a model assumption unless you have a real bank offer.
- Banks may quote different rates depending on equity, term, property type, and credit profile.


Interest rate

# Loan amount

This is the amount you borrow from the bank after subtracting your down payment from the purchase price.

Why it matters:
- It is the base amount used for interest calculations.
- It drives the monthly mortgage payment.
- It determines how much debt must be repaid over time.

Example:
- If the purchase price is `€500,000` and the down payment is `€100,000`, the loan amount is `€400,000`.

Important note:
- This does not include taxes and fees unless you finance those separately.


Loan amount

# Loan term

This is the total period over which the mortgage is expected to run.

It represents the number of years until the debt is fully paid off in the model, assuming the selected repayment pattern.

Why it matters:
- A longer term lowers the monthly payment but increases the total interest cost.
- A shorter term raises the monthly burden but reduces the time you stay in debt.

Example:
- A `30-year` term is often used as a planning horizon for comparison models.
- If the loan is repaid faster through higher repayment or special payments, the actual payoff date may be earlier than the stated term.

Important note:
- The loan term is a planning input here, not a legal requirement.
- Real mortgage contracts often have a fixed-interest period that is shorter than the full repayment horizon.


Loan term

# Monthly mortgage payment

This is the estimated monthly payment needed to service the loan.

Why it matters:
- It is the recurring cost you must afford each month.
- It is usually compared directly against monthly rental income.
- It is one of the main indicators of whether the property can carry itself.

Example:
- On a large loan with a modest interest rate and repayment rate, the monthly payment can still be several thousand euros.

Important note:
- This is a model estimate based on the interest and repayment settings you enter.
- Real bank offers may use slightly different repayment structures.


Monthly mortgage payment

# Monthly rent alternative

This is the amount you would pay each month if you rented a similar home instead of buying this property.

It is used to compare buying against renting over time.

Why it matters:
- It creates the baseline for your rent-vs-buy comparison.
- It helps calculate how much money you may keep if you choose not to buy.
- It can be compared against your monthly ownership cost.

Example:
- If a similar apartment rents for `€1,800` per month, enter `1800`.
- If rent rises over time, that growth is handled by the annual rent increase field.

Important note:
- Use the cost of a comparable property, not your current rent unless your current rent is the actual alternative.
- If you plan to rent a smaller or larger place, adjust the number accordingly.


Monthly rent alternative

# Net advantage of buying

This is the estimated difference between the buy and rent scenarios.

Why it matters:
- A positive number means buying looks better in this model.
- A negative number means renting looks better in this model.

Example:
- If buying leaves you `€50,000` better off than renting after the same number of years, the calculator shows `€50,000`.
- If renting leaves you `€20,000` better off than buying, the calculator shows `-€20,000`.
- In other words, the sign tells you which option won in the model.

Important note:
- This is a model output, not financial advice.


Net advantage of buying

# Cumulative principal vs interest

This is the point where the total principal you have repaid becomes at least as large as the total interest you have paid.

Why it matters:
- It shows when your money has gone more toward ownership than financing cost.
- It is a clearer long-term milestone than comparing only a single month.

Example:
- In the first years of a mortgage, interest usually dominates.
- Later, as the balance falls, principal repayment can catch up.

Important note:
- This is a model milestone, not a bank rule or legal threshold.


Cumulative principal vs interest

# Projected value

This is the estimated future market value of the property based on your appreciation assumption.

Why it matters:
- It shows how much the property might be worth after the holding period.
- It affects your estimated equity and break-even analysis.

Example:
- A `€500,000` property appreciating at `2.5%` per year would be worth more after several years if that growth rate holds.

Important note:
- This is a scenario estimate and can be wrong if the market changes.


Projected value

# Purchase price

The purchase price is the agreed value of the property before taxes, notary fees, land registry fees, or renovation costs are added.

Use the gross purchase amount you expect to pay to the seller.

Why it matters:
- It is the base for transfer tax in most calculations.
- It affects notary and land registry fees because those are usually tied to the purchase amount.
- It determines how much debt you need if you are financing part of the purchase.

Example:
- If the apartment costs `€500,000`, that is the purchase price.
- If you also pay `€35,000` in taxes and fees, the total cash required is higher, but the purchase price stays `€500,000`.

Important note:
- Do not include renovations here.
- Do not include moving costs here.
- Do not include furniture here.


Purchase price

# Renting cost

This is the calculator’s estimate of how much you would spend on rent over the selected holding period.

Why it matters:
- It is the baseline used to compare renting against buying.
- It helps answer whether the money saved by not buying might be enough to offset ownership costs.

Example:
- A monthly rent of `€1,800` for several years will add up quickly, especially if rent increases each year.

Important note:
- This is only the rent side of the comparison and does not include deposits or moving costs unless you add them separately elsewhere.


Renting cost

# Total interest estimate

This is the estimated total interest you will pay over the loan period in the model.

Why it matters:
- It shows the cost of borrowing money over time.
- It helps you understand the long-term price of financing.

Example:
- A lower rate or a higher repayment rate usually reduces total interest.
- Making extra repayments can also reduce this figure.

Important note:
- This is a projection, not an exact bank statement.


Total interest estimate

# Upfront cash needed

This is the total cash you need at the start to complete the purchase in the current model.

Why it matters:
- It is the actual cash hurdle before moving in or renting out the property.
- It combines your down payment and the purchase-cost total.

Example:
- If the down payment is `€100,000` and purchase costs are `€40,000`, the upfront cash needed is `€140,000`.

Important note:
- If you finance taxes and fees separately, the real number can be different from this simplified model.


Germany home buying cost model

Rental income

Property details

Mortgage

Hidden costs

Scenario controls

Buy vs rent

Purchase costs

Results