Financing options for a rather high-priced single-family house

you did not understand what I wrote, there does not have to be anyone watching you, because it remains a single-family house. However, you get double funding.

However, I do not plan an additional residential unit including heating, plumbing, and electrics and equip the apartment accordingly. If I don't do that, it is simply fraud. I have already understood what you are suggesting...

No, you still do not understand, not even what a housing unit is. The definition of the KFW is independent of the state building regulations. There is also nothing fraudulent about that. By the way, what I would be liable for,... But the KfW funding should not concern you further regarding the construction project.

The definition of the KfW is

...Residential units are rooms located in a closed context and intended for permanent residential purposes in residential buildings that allow the management of a household (own lockable entrance, room, kitchen/kitchenette, and bathroom/toilet) This is the literal definition of the KfW. How would you build the second residential unit if I understand it incorrectly? I am always happy to learn.

Thank you for the feedback!

I would leave KfW out for now, as we still don't know what kind of house we will ultimately buy.

Regarding the high price:

For us, that's a whole lot of money – we both come from a middle-class background and are only able to afford something like this thanks to inheritance/gifts.

Regarding the sale of the houses:

Of course, it's better for us if we can keep everything. How does it actually work if we don't sell anything and then end up in a worst-case scenario and possibly can no longer pay the installment:
- I lose my job and can't find a new one immediately OR become unable to work (I do have insurance, but it would only pay ~1.5k / month)
- No money as a buffer for whatever reasons

If the houses are used as collateral at the bank, what exactly are the consequences? Is it simply that the bank has to consent to a sale? What practical effects does that have (possibly on the achievable price)?

Regarding the installment / repayment:

- To what extent would the houses being used as collateral affect the conditions? At Dr. Klein I sometimes see 0.5-0.6% for 20 years fixed interest and 4% repayment. How much could this be improved with the collateral (rough estimate)?
- On special repayments: there will probably be inheritances at some point. But that could also happen only after 20 years. I will probably have a variable compensation component added next year (bonus). I have read that up to 5% prepayment per year is often possible without additional costs – anything beyond that usually costs extra. Is that right?
- Is there generally any reason against a higher repayment rate right from the start, other than the higher installment?
- What additional monthly costs besides the loan installment should be planned for – living square meters*3 for ancillary costs? Anything else?

Thanks again!

If the bank registers a mortgage on your debt-free houses, they have control over them. In the worst-case scenario, up to the foreclosure.

The discounts for special collateral vary from institution to institution. This reduces the risk for the bank per property, so the risk is spread over several properties, saving you the surcharges for a higher loan-to-value ratio.

Prepayment options also vary from bank to bank. But 5% is usually possible free of charge or at low cost.

There is actually nothing against a high repayment at the beginning in the case of an owner-occupied property, provided you can afford it and live well with it.

@

With 160-180m², a guest room with a kitchenette and a guest WC with a shower is usually no problem to designate, and no one has to rent it out. The access can be a room door from the vestibule.