We received 4% from the seller, but it was tied to the condition that we could no longer make any static or energy savings ordinance-related changes to our "Typenhaus." We are satisfied with the house, but there were some phases where we "regretted" that we had committed ourselves so much: I would have liked to have raised the attic higher or done the heat pump differently, etc. It is definitely the case that you don't get money for free, but instead you have to "restrict" yourself. For us, that meant: 1 day of sampling instead of 2. The outer house cubator can no longer be changed.