Construction costs are currently skyrocketing

Yes, me ;). After contract and signature and then after completion of the shell construction, the invoice was about 10K lower than offered

Is the boss by any chance your brother-in-law, club member, or did your grandparents already sing together in the same church choir?

No, but construction went well and it was already discussed beforehand that the invoice could be somewhat higher or somewhat lower depending on the final measurement and construction progress. The approximately 10K were then actually about 7% of the shell construction sum. I was really happy about that.

Well, that then has nothing to do with cheaper prices but probably only that the shell builder used less material than calculated...

Or has anyone ever experienced that after signing and clearing the right of withdrawal with their general contractor, they were called again because it became cheaper as the materials had become less expensive in the meantime?

By the way, I have experienced this too, with tiles that were then cheaper and with a staircase.

I also experienced that, but it was in 2017. 1) There was no contract or signature, only agreements and a handshake. 2) One agreement was, for example, with tiles, I get x% here and there, if you choose from there, half mine, half yours. 3) At the end during the final discussion he said, your construction went very well. I earned well from that. Therefore, I do not charge for the prefabricated garage, so reduce the final payment by 8500,- K.

Regarding 3) Wow, cool. I wish mine was like that...