First of all, thank you very much for your feedback - just for this alone, registering in the forum was already worth it :) What we are taking away for now is that the naive estimate of 350 T€ will not be sufficient, at least for this house size / this floor plan.
Apart from the costs, does anyone have any further ideas for the floor plan? Maybe it will have to be scrapped, although 170 sqm "in the village" is not exactly a huge construction project :)
Wouldn't it make more sense to build the garage downhill, maybe even integrate it quasi in the basement (partial basement)?
Somehow the floor plans don't look like the staircases line up vertically. On the ground floor the stairs also look too short.
Quite a few protrusions and recesses on the ground floor, what is supposed to become of that on the upper floor? Balconies?
We also considered a basement in a sloping site, but we want the garage to be close to the entrance.
The staircases do line up vertically, that is probably due to the presentation - I only took one screenshot each from the planning program... The stairs are not too short either, I took them 1:1 from the floor plan of the prefab house provider - we have even already walked up and down those stairs in the corresponding show house ;-)
The 2 bay windows or projections are only intended on the ground floor, we do not want any balconies etc. on the upper floor.
I don’t want to be a spoilsport, but have you had a normal size (as desired) kitchen island and a normal dining table (90 x 200?) drawn in? To me, that seems too generous for the dimensions.
What do you mean by "too generous"? The table is 1.35m * 2.31m (with chairs) and the kitchen island 1.60m * 0.9m.
So the same companies between Frankfurt and Cologne will be considered anyway. That already means prices are high. Plus a not exactly easy architecture drives the price up quite a bit.
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What do you mean by not easy architecture? For me as a layman it is ultimately a rectangular house with 2 projections / bay windows. Knowing well that bay windows are expensive. Apart from that, everything is kept quite simple. As I said, I am a layman without construction experience ;)