Provider selection prefab house: Bien-Zenker, Haas, Streif? Tips & Tricks?

Hello everyone,
great forum here :-)

We have a narrow plot and want to have it built individually (~13x6m). After a few rounds with some providers, it now seems to come down to a choice between Bien-Zenker, Haas, and Streif Haus.

The offers *seem* largely comparable; in terms of the personal touch, we have a preference (but of course, the salesperson is not the product!).
Price-wise, Streif Haus and Haas are roughly on par, Bien-Zenker is a bit more expensive but not yet negotiated.

--> Do you have any tips on what we should pay attention to?
--> Do you have experience with the specific providers Bien-Zenker, Haas, and Streif Haus?

Thanks to you! :)

For completeness:
We would have the houses fully finished each time because we are unskilled in craftsmanship and don’t want to handle it ourselves. We have the ancillary building costs in mind.

--> Do you have any tips on what we should pay attention to

1. Inform yourselves (a forum is a good start)
1a. Topics like yours are common. Use the search function.
2. Present comparability of the offers, Excel table with everything that is included and what is not.
3. If clueless, bring experts to your side.
4. Do not sign anything you do not understand.

--> Do you have experience with the specific providers Bien-Zenker, Haas, and Streif Haus?

See above 1a.

First of all, thank you! :)
Of course, we have already scoured the forum and also used Google - but to be fair, after extensive Google research, you really shouldn't build with anyone anymore. Happy homeowners rarely post...

We have created an Excel sheet and also cross-checked it with checklists.

--> The question is whether anyone was also in the direct selection situation between Bien-Zenker, Haas and Streif Haus and what they decided on. We have asked several experts, but it is vacation time. With the Bauherren-Schutzbund, we had bad experiences on the first attempt and have just started a new one (different advisor), but no response yet.
--> Do you have any ideas who could meaningfully compare the construction performance descriptions / offers for us?

Thank you!

We built with the former daughter BOS. You either like timber frame construction or you don't. Today I would prefer stone. But that doesn't necessarily have anything to do with Bien-Zenker. The house has been standing since 2006 and seems solid. Bien-Zenker is rather expensive, but apparently tends to be a bit difficult with defects. They also seem to have very full books at the moment. I read that on FB.

Nothing signed before you know the price, we even had the window color, the shape of the stairs, the finished floor plan, tiles, fireplace ventilation, heat pump, everything included in the offer. After the signature comes the sampling and the empty wallet.

And the word bauseitzt is your problem

Did you have conversations with regional construction companies?