Looking for a large house construction company in Regensburg - experiences, tips?

Hello dear forum,
my wife and I want to build a single-family house next year.
At the moment, we are still finding and analyzing the different house construction companies on the market.
Unfortunately, many companies demand a horrendous price.

Therefore my question to you.

Do you know house construction companies from Regensburg and the surrounding area that build cheaply?

I look forward to your answers.
Best regards

Cheap and Regensburg unfortunately do not exist...