Assignment Declaration of Credit

That is indeed property. Not directly bad yet. The question is how exactly the contract is structured. For example, it cannot be that the construction company gets direct access to the account. You have exactly one (in words: one) leverage against the construction company if there are defects during construction. And that is your money. And you must not give up this leverage.

Nordanney, you are right. Unfortunately, I do not yet have the documents from the bank and the developer. However, I have already opened the account. It was explained to me over the phone once. But unfortunately, I am not a banker and have not studied financial law.
In essence, I open a daily allowance account. I give the bank a SEPA mandate on my account (in this case, my checking account). Then I set the reference account to the developer’s account. Then I transfer 20% of the contract/house construction/service contract sum to the daily allowance account. The bank withdraws from my checking account. And then I and only I can pay the installment payments (only!) online to the construction company. And nowhere else. The construction company does not have direct access to my daily allowance account. I just have to be careful not to have more money in my account than I have to pay. Because then I probably cannot access it myself anymore.

With regular savings accounts, there can be at most one savings bank, and that only with associated costs.

And with assignments... well, what kind of developer is that? More in the low-budget range?

An assignment means that you can practically never access your money & if there is ever a dispute, you can never switch the developer.

You can, but then without your money. There are legal disputes. I also don't know how that works in the case of insolvency...

I am with Berny. I would never do something like that. When our general contractor (GU) came with something like that, we said, Mr. S., we trust you to build the house for us and give you our word that we can and will pay for it. Every interim invoice, within 8 days with discount, within 14 without. He agreed to that. Handshake on it, and that’s how it was. If the GU doesn’t want that, he is the wrong one for me. K.

I agree with Berny. **If the general contractor doesn’t want that, he is the wrong one for me. K.

Berny doesn’t mean anything to me now. Google finds Bauberatungsnetz der Bauherren?? The problem is that we have already signed and also want to build with the construction company. Are they even allowed to include such a clause for homeowners with private assets? What annoys us is that we are introducing an uncertainty with the described account here - so a risk for us - even though we have the money under our mattress. And the costs for a notary (escrow account) are not insignificant according to our construction company. The amount is supposed to be four digits.

Berny is a user here who said something about it before... it's quite simple: You have money, and they want to sell the house. if you don't want to deal with them because of this clause, then tear up the contract. I could understand that. Or, they believe you that you will pay. You also have to believe them that they will build properly. Possibly, one could find a way to say: For every payment step, we start with one-third of the down payment from me, then you build, then the rest is paid when you are finished... then the next step the same way. Or do you pay everything in one amount?(Scanhaus Marlow). K.

Are they even allowed to include such a clause for builders with private assets like that? (…) even though we have the money in cash under the mattress. (…)

According to § 650 m of the Building Code (new version) (for the new consumer construction contract according to § 650 i Building Code): Yes, up to the 20% limit. § 650 m can also be waived – even to the detriment of the consumer – see § 650 o, which explicitly excludes lit. § 650 m Building Code. This furthermore modifies the regulation in § 650 f Building Code on security deposits in the context of the construction trade security, which there applies more to contractors than consumers – these are explicitly exempted from § 650 f (VI) Building Code / are not required to provide security. But that is also dispositive (see § 650 f (VII), which does not mention paragraph 6 there. And § 650 m Building Code takes precedence over § 650 i (III) Building Code. And: Cash under the mattress = freely available / collectible = risk for the construction company (even if of rather academic nature).