General contractor / prefabricated house provider with an existing BG (HOAI Phase 4)

Screaming? :rolleyes: But nice that you understood it now.

That may be, but the purpose of the ! is usually not to indicate shouting but (when in brackets) to draw special attention to something. ;) In this case, it was about the fact that a GU (and not a GÜ, which is often used synonymously) is being sought here.

But one more thing about the actual topic: Tell me exactly where in NRW you want to build. For such a project, generally the smaller GUs are more suitable, which usually only operate regionally.

What I still haven’t quite understood:

The companies we spoke with (and there were quite a few) were not able to address our requirements and the particularities of the property in enough detail, at least not before signing the construction contract.

This hurdle has now been removed, the one who better understands the requirements aka the architect has been found. Was there none of the "quite a few" companies with whom one could have started right away – what now speaks against it (apart from my recommendation for tendering and architectural site management)?

I would just be interested to know where the truly unsolvable problems of the property are. Please upload the development plan and the property plan.

My wife and I have purchased a plot of land and were initially looking for a general contractor or a prefabricated house provider who could offer us a move-in ready house at a fixed price. This was important to us because we have heard many negative experiences with price explosions when building with architects.

The price explosions are NOT due to the construction method with architects. Do you mean that the GC or similar can build cheaper? Material prices and labor costs are more or less identical (many of them subcontract their orders anyway, which you might have hired yourself in a build with architects).
The GC/prefabricated house provider is better and cheaper if you buy/build a standard house. There is not much planning involved and it has been built several times before. No new plans to draw, no new structural analysis, etc.

If you go to the GC with your architect’s plan, he will give you an individual price and directly add possible cost increases. It definitely won’t be cheaper.