Hello,
bo is schon ganz schön viel
ich habe gedacht ich komme mit 260T€ hin plus Baunebenkosten
That is quite a big house :-) In addition, you have come up with some rather expensive gimmicks, such as the WC in the basement, 4 bathrooms, the integrated garage, or the hip roof – everything has its price!
Heizung soll eigentlich Gas sein und Solar als Unterstützung, dann habe ich auch noch Lüftung mit im Plan,
The base price I quoted you includes the gas condensing boiler and solar domestic hot water heating. If you want a controlled residential ventilation system with heat recovery, you realistically have to budget around EUR 12-15k depending on whether parts of the basement are to be connected or not, given the size of the house.
Elektro kann man mal Rausrechnen die kann ich in Eigenleistung machen,
Not a good idea; electrical work should always start where the contractor’s scope ends => warranty.
So if electrical work is planned as self-performance, you should also remove all subsequent services: screed, drywall, interior plaster, tiles, interior doors, sanitary final installation, as well as painting and floor coverings from the contract. If no concrete staircase is planned, the above applies equally to the wooden staircase construction.
und Trockenbau wollte ich auch selber machen, wo kann ich noch sparen?
Tapete oder Putz und Fliesen kann ich nicht will ich auch nicht probieren (das geht schief) aber vielleicht die Fußbodenheizung verlegen?
The above also applies to installing the heating loops.
You can save money by choosing a different roof shape, removing the WC in the basement – it requires a macerator with 2 motors – and finding another place for the garage. If the garage is integrated into the house, the room where the cars will be parked must be constructed according to different regulations than a "normal" utility basement. Of course, the most savings come if you forgo the basement altogether.
If everything is to remain exactly as is, you have to come to terms with managing a total volume of "so far" about EUR 414k.
Kind regards