Hello,
I am not allowed to provide legal advice, this is exclusively reserved for consulting professions in Germany!
The contract with the construction service provider states in the construction and performance description under general: The maximum construction time is 6 months without a basement, 7 months with a basement.
Is that a guarantee that you can hold him to?
In every contract for work, there is a ranking of precedence, i.e. as a rule the contract for work - based on the BB - takes priority. If additions are made, they must generally be observed over the contract for work - unless there are other formulations.
So you have to check whether your contract for work contains a different formulation regarding construction time. If the contract for work and BB correspond to each other and there are no other changes in the form of an additional agreement regarding construction time, the construction time stated in the BB applies.
When we said for the last invoice that the work is not yet as far as we want it, so we first don’t want to pay this invoice, he immediately said he won’t come anymore. He also did not agree to the proposal of a security account. So we paid...
Sorry, but very stupid... you should never give in to blackmail! Besides, the shell builder is not allowed to do that either, he must adhere to his contract just as you must adhere to the agreed payment steps in your contract for work.
Rhenish greetings