Which financing is better...

Z15 doesn't fit for you? Income slightly too high?

2x building savings contracts also means 2x contract conclusion and account maintenance fees and the deposits are not/almost not interest-bearing. Is all that included? What happens to the 70 and 100k€ after 10 years? If building savings contract, then without Riester. You have to accrue interest on the construction promotion account for almost 20 years. Riester only for the woman with child allowance and funds.

Combination loan Sparkasse/LBS: Wife €95,000 installment €317 over 20 years, effective annual interest rate 0.20%, unlimited special repayment option (bullet loan is redeemed after 13 years through building society savings contract. Low interest rate due to Riester subsidies wife + 2 children)

so for 0.20% effective over 20 years, then the interest rate at the Sparkasse would have to be below 0.10% nominal for the first 10 years, and then another 10 years nominal also below 0.10%. So that you get 0.20% for 20 years while taking into account the 1% closing fee!

with the LBS you have to keep in mind that for the loan you draw, they also take 2% discount. So the loan should be completely interest-free and only consist of discount/closing fees!

or it runs through a promotional account (Wohnriester) and they calculate the subsidies (2 people + 3 children) and so they come to 0.20%?

because in the end the promise is that you can get into better retirement provisions with higher returns (which is the purpose of retirement planning!)

and you don’t have to pay taxes on everything in retirement because you have built up a Wohnriester promotional account, which is dissolved at retirement and then suddenly you owe several thousand EUROS in taxes (and then the 0.20% effective doesn’t add up again!!!)

I don’t understand why people don’t clearly separate:
retirement provision = retirement provision
home financing = home financing
and people "believe" the people that Wohnriester is cheaper?

Z15 doesn't fit with you? Income slightly too high?

Thanks for the idea with Z15. I had also looked into it at the beginning, but then discarded it... We have already signed the construction contract. You have to apply for Z15 in advance. So that ship has basically sailed. I excluded Z15 for myself back then because it is very rigid. Only low repayment (2%?) and no special repayments. After 15 years, a lot of residual debt remains. We would like to repay faster and more. Of course, you could now put the money into a daily allowance account and then repay the loan accordingly after 15 years. But I don't feel good about the idea of having so much money poorly interest-bearing in the daily allowance account. It is only secured up to a limit in case of bank failure, etc. At some point there might be negative interest rates. Ideally, I would simply repay immediately through special repayments as it fits and save interest. The house bank doesn't like that either because they want to be first in the land register. That's why we would need a more expensive supplementary financing through the L-Bank since Z15 does not cover the entire financing requirement. Also, I had the impression that the application takes a very long time and is very bureaucratic... We actually need a financing commitment soon... That's why Z15 doesn't fit perfectly even if the good interest rates are tempting. But the interest rates at the house bank are not much higher for 15 years either. But we actually want 20 years for peace of mind.

2x home savings contract also means 2x contract and account management fees and the deposits are not/ barely interest-bearing. Is all that included? What happens with the 70 and 100k€ after 10 years? If home savings contract then without Riester. You have to bear interest on the building promotion account for almost 20 years. Riester then only for the woman with child allowance and funds.

Good arguments, thanks. Yes, I don't want to include Riester. The building promotion account doesn't sound good. Only the government could come up with something like that. Lots of bureaucracy and not transparent. Anything I can't calculate myself in Excel I actually don't want...

or it runs through the funding account (Wohnriester) and they calculate the allowances (2 people + 3 children) and that's how they come to 0.20%?
(...)
and you don't have to pay tax on everything in retirement because you have built up a Wohnriester funding account, which will be dissolved at retirement, and then suddenly you would owe several thousand EUROS in taxes (and then the 0.20% effectively doesn't add up again!!!)

Yes, exactly. Wohnriester is included (allowances for 2 adults and 3 children). The costs for the housing funding account are not included. That's why the interest rate is low. I decided that it is therefore not an option.

I don't understand why people don't clearly separate:
retirement provision = retirement provision
home financing = home financing
and people "believe" the others that Wohnriester is cheaper?

Thank you! A very helpful comment. Helped me on our decision path.