Financing question for our construction project

Should one take the offer? Or should something be optimized? In view of KFW, I find it difficult to pay off the "cheapest" loan so quickly instead of investing 400,- (almost 50 euros of interest have to be paid anyway at KFW) more into the repayment of the expensive bank loan to get rid of the remaining debt faster... does the offered option from the banker make more sense??
Maybe you have a tip for us. Thank you very much :)

I find the installment a bit high. But you have to know that yourselves.
Maybe you go for a longer term band with the KFW loan. Then you will still have a certain residual debt after 10 years. If the assumed total installment fits, you can increase the installment on the bank loan. But overall, the package would suit me.

No, KfW 70 is at 1%. at least this morning ...

KFW also adjusts its conditions not only downwards :)

Total construction sum 470,000,-
pure land price (already paid) 98,000,-
construction costs (standard will be KFW70) 370,000,-
remaining own capital 130,000,-
thus there is a financing requirement of 240,000,- of which 50,000,- comes from KFW153 at 1.0% and 190,000 from a classic bank loan.
Our net income 4700 euros - since there are no children yet but 2 are planned in the next 2-3 years, some flexibility in financing is desired. Changing the rate or temporarily pausing the KFW repayment would be an option.

Are ancillary costs, exterior facilities, kitchen, furniture, buffer, etc. included in the construction costs? Otherwise, you should definitely still do that.

The KfW also adjusts its conditions not only downwards :)

I know that too :P. But I find it amazing how quickly everything is happening right now. And under the circumstances, I am now securing the conditions for myself, because the offer sounds good.

I know that too :p. But I find it so amazing that everything is happening so fast right now.

That fast? They increased by 0.15%. Should they increase the conditions by 0.01% daily or how would a slow increase look like to you?

By the way, I also took out my KfW loan with 1% interest and was then amazed at how quickly it dropped to 0.85%...

Yes, the property is completely free of encumbrances! Additional costs (notary, etc.) have also been paid from equity. The construction costs already include kitchen, outdoor facilities, buffer, etc. KFW has definitely been at 1.0% for a few days now, we were unlucky, but whatever... :) We also like Jochen104's idea to extend the KFW term; if there is anything left at the end of the year, we can make special KFW repayments. Schemelino (among others) also pointed out that the installment might be too high. However, we carefully calculated our expenses and I found 1450/month overall manageable... I will really use the calculator again! An intermediary could not provide a better offer - we are a bit of a special case since I, as a Frenchman with residence and tax domicile abroad, fall outside the scope of many banks (at least according to statements from Interhyp and an independent broker). That is why we also went to the local bank that responds better to such cases. The installment can be changed free of charge up to 3 times within the fixed interest period.

That fast? They raised by 0.15%. Should they increase the conditions daily in 0.01% steps or how would a slow increase look like to you?

I actually mean "fast" as the response time, not the amount. To me, that somehow suggests that the increase could continue further.

By the way, I also took out my KfW loan with 1% interest and was then surprised how quickly it dropped to 0.85%...

Oh, so you were surprised that it happened quickly after all? ;)