House construction and sale - current residential property

However, the interest rate for the bridge financing is correspondingly higher.

What are you paying? It is also financing without collateral = without a mortgage. Probably somewhere between 2.5 and 3%. You can finance the interest costs as well.

What are you paying? It is also a financing without collateral = without a mortgage. Probably somewhere between 2.5 and 3%. You can finance the interest costs as well.

It is 3%

Is it possible to take the money "normally" with the financing and negotiate with the bank that, for example, you could pay back 100k or something similar, so that you save on the interest?

Is it possible to take the money "normally" with the financing and negotiate with the bank, for example, that one could pay back 100k or something similar, so that you save the interest

It is a variable financing, which can be repaid daily (unless you finance via the Euribor). So quite relaxed.

Only at some point, [Bereitstellungszinsen] will presumably become due there as well.

... and thus the original poster would have to finance significantly more if he does not sell the house. Which he might be able to do thanks to the rental income (maybe), but his situation is identical to the option where he sells the house.
How a bank evaluates this, when taxes and management costs are deducted from the rental income, is another topic.
Not to mention the rental risk.

Therefore, it is always an individual case-by-case decision. You simply cannot say in general that renting out is better than selling or vice versa.

There is practically no difference.

I see it differently. A condominium/semi-detached house is usually rented out faster and at a higher price per square meter than a single-family house, which is why the latter fortunately mostly do not serve as yield objects and thus are not bought by investors.

???

Condominium/semi-detached house: income value usually higher than material value
Single-family house: material value usually higher than income value

I consider that a bold thesis.