Hello,
I would absolutely advise against Rensch-Haus!
The construction phase went without major problems. However, after three years we had the first water damage and one and a half years later the second water damage. The ground floor was completely renewed in both cases with screed, etc. Our house was uninhabitable for half a year the first time and we had to leave our house for 10 months the second time due to water damage. There was no support from Rensch-Haus.
So stay away.