Opinions about the offer

So it is then 171 liters. All good.

150L is too little for gas including solar, but the general contractor offers it.
And that shows that you should really check everything.

Ok, you like to read such things just to be made aware!
But is the variant with the heat pump better now, really unsure whether heat pump or gas..

The surcharge for the heat pump is not insignificant, and if it is not well planned, it may end up costing more than the gas heating system in operation and everything else.
In the "Heizung" area, there are threads on this topic. Have a look there.

At 1400/sqm, I would personally be a bit cautious with today's knowledge.
We were already relatively cheap at 1600/sqm in Lower Saxony in 2013. Especially since upgrades of 30,000 (including EL) are already factored in.
Nowadays, for example, I wouldn't use gypsum plaster anymore, etc.

Get another offer from a different BU (but not Heinz von Heiden) and roughly compare the construction service description yourself, often you can already see the difference there.

I took a look at the electrical section. My parents' house from the 70s is better equipped in that regard. There will still be quite a few sockets, switches, but possibly also lighting points to come.

Telephone sockets are no longer installed today. What are 2 empty data boxes? LAN? Do the cables in the utility room go to sockets or are they hanging freely in the room? In any case, 2 LAN sockets are too few nowadays in a new building.

Is one antenna socket enough? The antenna cable only goes to the utility room or under the roof. Satellite system, for example, is not included.

Roller shutter with strap pull? I would change that too. In new buildings, I definitely don’t install straps.

Opinions are so different.. For example, [keine elektronischen Rollladen] are not needed!