Financing a New House: Is Mortgage Swap Sensible or Not?

I can only terminate the loan with a prepayment penalty.
I can't imagine that it would be worthwhile for me.

Have them calculate it for you.
Don't forget that with a new loan you will get a much lower interest rate, which you will then probably have for at least 15 years. On the other hand, you have to factor in the 10 years (at least 5, because you also have a right to terminate after 10 years) with the higher interest rate.

That would be the first bank I see that waives justified prepayment penalties. You have hardly repaid anything so far and still have 10 years of term, so there is substantial prepayment penalty. A swap of collateral certainly makes sense, but the bank has to agree to it (think about arguments why they should agree.... they will get their 15 years of interest anyway). The swap of collateral also costs money at the notary and the district court – more than a new land charge registration for a new loan.

Small update:

Fortunately, we now have no financing gap and can simply continue financing the house with the existing loans.

I have one more question about the costs incurred for the pledge exchange at the building society: They now want €500 just for the review to determine whether the pledge exchange will be accepted. Whether there will be additional costs, I do not know at the moment. To be honest, I find that a bit steep given the low value of the loan. Is that normal?

I couldn’t quickly find a price/performance list of Sch.Hall that includes the costs for the pledge exchange. Does anyone have a tip on whether that is available online?

Thank you very much.

I honestly find that a bit steep given the low value of the loan. Is that normal?

Completely normal. It requires a lot of personnel effort.

What effort is supposed to be 500€, I really don’t understand. Any craftsman who writes me a cost estimate for free is probably occupied longer with that.

I don't really understand what effort is supposed to be involved that amounts to €500.

Handling files and securities, property appraisal, correspondence with notaries, appointments with notaries, loan approval, contract drafting, correspondence with customers, generating revenue. The employee easily costs €100 per hour and could deal with new business generating revenue instead of trifles (like pledge exchange).