Financing - Special Termination and Deadlines

What would be the most sensible thing to do in this situation?

Depends on loan volume/interest/repayment etc. What was financed in 2013 under what conditions and how? You can directly restructure KFW. If another bank, then possibly take the regular loan directly via forward contract.

What was financed in 2013 under what conditions?

101,000€ main loan with 3.5% 50,000€ KfW with 2.6% (ends 09.2023) Signed October 2013 Disbursement of the last 2,000€ in November 2014 Fixed interest rate until 09/30/2028 Annuity repayment is 3% In January 2021, the remaining balance was 90,900€ Building savings amount 40,000€, balance at allocation 09.2023 20,700€

€101,000 main loan at 3.5%
€50,000 KfW at 2.6% (ends 09.2023)
Signed October 2013
Drawdown of the last €2,000 in November 2014
Fixed interest rate period until 09/30/2028
Annuity repayment rate is 3%
In January 2021, the remaining balance was €90,900

Building savings sum €40,000, balance at allocation 09/2023 €20,700

Unfortunately, I am not familiar with building savings constructions.

With a classic annuity loan, you would have a remaining debt of about €80,000 on the "big" loan after 74 months.
How do the €90,900 break down? Is the repayment actually less than 3%? Does part of it flow into the building savings?

What are the current monthly payments?
€101,000 (interest 3.5%, repayment 3%): €547
€50,000 (interest 2.6%, repayment (assumption) 3%?): €233 or €700 quarterly
And how much do you pay into the building savings?

The 90,000 consists of 47,000 main loans and 43,000 KfW. That is not supposed to decrease. 731€ go to the bank every month and independently from that, another 183€ into the building savings contract. It was only intended for saving and in case the interest rates climb back to 6% when we want to finance the follow-up loan. The 3% repayment is stated like that in the contract.

The 90,000 consists of 47,000 main loans and 43,000 KfW. That one does not want to decrease.
731€ go to the bank every month and independently of that another
183€ into the building savings contract. That was only intended for saving and in case the interest rates rise to 6% again when we want to do follow-up financing.
The 3% repayment is stated like that in the contract.

Your numbers do not add up. You need to check your contracts again.;)

However, it is interesting that my 547€ and your 183€ add up to about 731€.

Remaining sum of 47,000€ does not fit with 3.5% interest and 3% repayment at this term.
And if the 731€ go directly into the large one, 105 months would have to have passed to reach a remaining debt of 47,000€.
And the 183€ into the KfW, that is how you reach the 43,000€.

Your numbers don't match up. You need to look at your contracts again.;)

The numbers are from the contract. The folder is next to me.

But it's interesting that my €547 and your €183 add up to about €731.

The €731 is purely the total repayment of the loan and the KfW.
€183 is additional. So €914 go to the nice financial service providers.

Remaining sum of €47,000 does not fit with 3.5% interest and 3% repayment over this term.

We have used the option of special repayments a few times. A few times it was €5,050.

And the €183 to the KfW, then you come to €43,000.

10a*12M+€183 I come to a theoretical ~€22,000

There will be no more special repayments for the time being, as I am now building an extension in parallel.
For that, the last cash reserves are supposed to be used up.