Semi-detached house architect or general contractor / prefabricated house or solid construction

Hello, I am completely new here and still very early in the planning:

We are going to build a duplex, the only question is what the best approach based on experience is: prefabricated house in timber frame construction (we know someone there) or solid house: the prefabricated house is said to be not so good especially in soundproofing or only at high costs. But with a duplex, that could quickly lead to problems between the two halves of the duplex, right?

Should we simply request offers from house construction providers (e.g. Massivhaus Mittelrhein, Zenz Hausbau) and discuss everything with them? Or a variant with an architect? 1. Completely with an architect, although our friendly architect is not from our region. Does it still make sense to commission him for all service phases (i.e. including awarding contracts, supervision, coordination)? 2. Or have the architect only make a design and then look for and commission a general contractor, and at least have the architect check the general contractor contract?

Oh, so many more questions are pressing. But maybe your experiences can already help me a bit

Thanks, Caroline

I would assume that even with prefabricated houses in the semi-detached house style, the requirements for soundproofing (the wall between the houses) are met - I was wrong, if you believe Epi's website not bad - you rank first when you enter semi-detached house and soundproofing. I can recommend this to you, very informative

what is epis Website?

Moderator, construction expert, look at the profile, their website should be listed there

OK, thank you.
Are there also answers to my questions?

What exactly do you have in mind? Is insulation a problem for you or do you view it positively? How do you want to heat the house? Have you been to the model home park to look at houses and do you have a favorite or two?