Lost trust in sales representatives

Oh yes - you have probably already seen this thread? https://www.hausbau-forum.de/threads/lechner-massivhaus-erfahrungen.24296/

That after such behavior of the seller, one even thinks about building with them. Always remember: scoundrels usually work with scoundrels.

And even if not. You apparently have no detailed construction service description. Even if the house builder is not a scoundrel. He only delivers what is stated in the construction service description.

I would not save on the windows. The police generally recommend RC2 for the bottom, in densely built residential areas also RC2N. Because attacks on the glass are rather rare.
At the top, it can also be RC1, as long as the window cannot be accessed via adjacent roof surfaces. Choose RC2 all around and you are on the safe side.
A thief must suspect pure gold with you to bother breaking an RC2 window. The neighbor usually has normal windows, so he just goes there.

Roller shutters do not protect you from burglary. The normal version is simply pushed up by the burglar, the window is broken, the roller shutter is lowered. And then he can basically live there for a few days, no one notices.
If you have roller shutters with a security class, they only help if you consistently keep them down all the time. Or you need additional security windows... which is somehow nonsense.

I can't tell you anything about soundproofing. We have U 0.5 and RC2 as standard. But do you really need RC2 for a single-family house? I would ask you if roller shutters are included, and if so, whether they are electric? With us, aluminum roller shutters (electric) were standard. With many cheap providers, this involves an additional cost.

The electric ones cost extra. But I only saw that in the construction service description. Basically, it can be said that the standard is rather lower. So, for example, only RC1 windows everywhere.

I took a look at the website, the wall elements apparently already have the rough installation and base plaster. So they are much closer to the wooden prefabricated house than to conventional solid construction. But construction is especially slow (whether prefabricated or conventional) mainly if the contractor is poorly organized and there is a lot of downtime between trades.

Exactly, the wall arrives finished, no need to make grooves or anything like that. We found that appealing.

So long doesn’t stone on stone take either. The pure gluing of the Ytong stones takes less than 2 weeks for 2 floors. What total construction time did they promise you?

We would already be living in it after one year. Construction was supposed to start right after the planning approval this summer.... but well, who knows if that was true.

That you even consider building with them after such behavior from the seller. Always remember: scoundrels usually work with scoundrels. And even if not. You obviously don't have a detailed construction performance description. Even if the house builder is not a scoundrel. He only delivers what is stated in the construction performance description. I wouldn't save on the windows. The police generally recommend RC2 at the bottom, in densely built residential areas also RC2N. Because attacks on the glass are rather rare. Upstairs it can be RC1 as long as the window can't be reached via adjacent roof surfaces. Take RC2 all around and you are on the safe side. A thief has to suspect pure gold with you to bother breaking an RC2 window. The neighbor usually has normal windows, so he just goes there. Roller shutters do not protect you from burglary. The normal version, the burglar simply pushes up, breaks the window, lets the roller shutter down. And then he can basically live there for a few days, no one notices. If you have roller shutters with security class, they only help if you consistently keep them down. Or you also need security windows... which somehow makes no sense.

It is indeed not detailed. 25 pages, with 1/2 to 3/4 of each page only pictures and sometimes only 2 sentences. When I compare it to other providers that is true. I have told him several times that I need more details, I want to know what they do and where we start since we also take trades out. Later it is difficult to argue if you don't know who has to do what. We only have venetian blinds on the ground floor, roller shutters only on the upper floor, so I think RC2 makes sense.