Special repayment, saving or consumption?

Well, I understand that the plots cost different amounts. But if a solid house today in Erlangen (just the house) costs 500,000, does it then cost only half that amount elsewhere in Germany? Material and so on don't make a difference.

Well, I understand that the plots have different prices. But if a solid house today in Erlangen (just the house) costs 500,000, does it then cost only half as much somewhere else in Germany? Material etc. doesn't make a difference.

A solid house doesn't have to cost 500,000 euros even today. It depends on the size. You can still build 100 to 120 sqm for 250,000 to 300,000 euros.

I see it the same way.

Ultimately, debt is debt. Whether it is worth more or less doesn't matter to us.

We have secured our financing for 10 years and will also make sure to keep the remaining debt as low as possible in the end through special repayments and increased amortization.

With 3-8% inflation, you don’t make special repayments with a 1-2% loan rate. That’s a great return! You’d rather invest the surpluses in the stock market or in additional equipment (pool, pool house, possibly photovoltaic system, etc.).
I once calculated it. We agreed on a 30-year fixed interest rate of 1.63%. In 30 years, we will pay around €67,000 in interest, so not even €190 per month (imputed cold rent) for a house.
Since there is an equivalent value to the debt that increases over time (just through inflation) while the debt gradually decreases, I prefer to consume the household surplus or invest it in investment forms with a return above inflation.
We will probably inherit well, and I wouldn’t be foolish enough to repay the loan with a 1.63% fixed interest rate using the inheritance; instead, I would invest the money with a 5-8% return. This way, there is a 3.37-6.37% additional income on the full amount, which alone can cover the loan payment. The loan will quietly run until the end of the term/fixed interest period with a €908 rate (of which an average €186.11 is interest and €721.89 is savings/repayment).