Who has experience with Bonum Haus GmbH?

With Bonum Haus, the client makes a direct contract with the construction management.

From Bonum Haus.
And not chosen by yourself.

I have to correct you. With Bonum Haus, the client makes a contract directly with the site management.

what then, in your opinion, does mean by this statement?:

Yes, Bonum only mediates the craftsmen from the region for you. However, site management/supervision is included as well.

From Bonum Haus. And not selected by yourself.

That would be the ultimate mockery squared.

On the subject of site manager / "site manager", I recommend my posts here:

From that perspective, I naturally find it kind of stupid that there is no independent body overseeing it.

In the bonum brochure, the topic of quality is advertised by stating that through years of collaboration among the trades, the quality is right and that they have a sophisticated quality system that catches errors. I have no idea what to make of that.

From this perspective, I find it somehow annoying that there is no independent body checking.

No one is stopping you (and you shouldn’t forgo it) from having someone professionally qualified represent your quality interests on your construction site and monitor their preservation.

In the bonum brochure, it is advertised under the topic of quality that through years of collaboration between trades the quality is right and that they have a sophisticated quality system that catches errors. No idea what to make of that.

If a provider cannot convince you transparently, then "keep your distance" and choose one of their competitors. In this section, many prospective builders ask about companies X and Y because they are the only ones they have heard of so far – but there are also Z and A through W (and by the way some posts in which several of these competitors for the respective building region are listed and even comparatively classified).

Basically, I can't say anything negative about Bonum. They actually only refer regional craftsmen.. However, if there are "serious" problems, the site management reminds 3-4 times.. but no more than that.. We didn't have any major defects.. But I do strongly recommend a concrete inspection for basement construction.. That was/is our problem child

Betongutachten

Soil survey report? I always wonder, when I read something like with this company here, who later wants and can manage years of legal fees in two directions, because the T&Cs in the contracts are written to be safe - just not for the one who builds.