Building savings loan with building savings contract

Good morning everyone! I am now trying to put everything together as I have understood it. There are two loans: the first 230,000 (1,100 installment), L Bank 100,000 (434 installment). Building savings contract - 150,000 (260 installment instead of 215, so the saver would be eligible in 2036) + 2,500 annual special repayment. That results in 1,794 + 210 special repayment = 2,000 euros installment. And yes, we can afford that. The special repayment is suggested by me (half of our vacation and Christmas bonuses). From 2036 on, the saver repays the L Bank loan of 100,000. The monthly installment then amounts to 1,100 euros (main loan) + 750 euros (building savings contract) = 1,850 euros. The long term of the main loan bothers me a bit (until 2057), possibly shorten it with special repayments. During the next week, I will try to get an offer for an annuity loan from Interhyp. Then we can probably compare both options. I will post here again. I thank you for the quick answers and assessments and wish you a nice weekend!

The long term of the main loan bothers me a bit (until 2057), possibly shorten it with special repayments.

The term is always calculated to about 30 years, I wouldn't mind it at all. And yes, you can probably make special repayments on the main loan with a standard maximum of 5% annually. You don't have to, you can. This way you pay off the financing faster.

Starting from 2036, the building savings contract will replace the L-Bank loan of 100,000.

Why is the building savings contract then designed for 150,000€ instead of 86,000€?
Securing the follow-up financing of the L-Bank loan only makes limited sense anyway, since the main loan also expires after 10 years. From my point of view, this would only make sense if the main loan had an interest lock-in period of at least 15-20 years.

Hello everyone! As promised, I got an annuity loan offer from Interhyp.
Purchase price 310,000.
Broker commission 11,067.
Costs for notary and land registration 6,200.
Real estate transfer tax 15,500.
Less equity 19,767.

Financing requirement 323,000.

Partial loans:
Sparda-Bank Südwest - 230,000, nominal interest rate 4.26, effective interest rate 4.37. Fixed nominal interest rate for 10 years, remaining debt after 10 years 150,638.27. Monthly rate 1,095.50. Term 26 years and 10 months.
Sparda-Bank Südwest - 13,000 (consumer loan) nominal interest rate 6.10, effective interest rate 6.31. Paid out after 15 years. Monthly rate 110.50.
KFW 124 - 100,000, nominal interest rate 3.80, effective interest rate 3.90. Fixed nominal interest rate for 10 years, remaining debt after 10 years 72,605.47. Monthly rate 316.67 (the first year), then 529.81. Term 25 years.
And all this results in the monthly rates:
1,522.67 in the first year.
1,735.81 for the next 25 years and 10 months (calculated).
After 15 years 1,625 (no more consumer loan).
I can confirm that the annuity loan looks much simpler. I ask the professionals here for a comparison with the combined loan from the Sparkasse. I can only say – the offer from Interhyp has lower monthly rates and a shorter term. Or am I overlooking something? Thank you in advance!

Or am I missing something?

What does the structure cost you over the term? That is, interest until full repayment

I cannot really understand the term of the first loan (230K€). If the interest rate remained the same after 10 years, in my opinion, that would be a term of 32 years. The remaining debt of 150K€ after 10 years also does not add up; there must be special repayments of around 3,000€ per year in order to reach 150K€ after 10 years! I have similar terms for the other loans. If special repayments are planned, I would prioritize making them on the consumer loan. For the assessment of the term, I cannot evaluate the savings bank loan at all, since the refinancing through the building savings loan is not taken into account. Also, after 10 years, one should assume at least the same interest rate for both options.