Ideas for floor plan adjustment of house with extension on the west slope

200000 sounds pretty decent already. Sorry for the accusation above! I would say it is exactly the boundary between "new construction is worth it" and "more than renovation is not possible." With that budget, it really is not an easy decision. But sinking 200000 into a less-than-optimal house is, of course, not without its challenges. In the worst case, you always have to deal with "if we had invested a bit more back then, we would be living in the dream house now."

The windows are the smallest problem, since we ourselves have a window and shutter construction business. Custom-made windows are standard here.

I can confirm that. The idea that windows in "standard sizes" are cheaper applies only to specific hardware store stock sizes in white single-leaf tilt and turn, triple glazed, but otherwise standard glazed.