The big "controversial issue," presumably every source will preach to you the supposed advantages of the construction type. In my opinion (having helped build both to a large extent), a prefabricated house has mainly advantages if you yourself want to do a lot of installations (water, heating, electricity, etc.) or generally very much do-it-yourself work. For the installations, for example, all the chasing work is eliminated, and it is also easier to screw drywall sheets onto a wall and plaster them than to plaster a wall. In addition, better thermal insulation is possible with thinner walls if the building window is tight. If you have enough space and opt for turnkey construction, in my eyes almost all advantages disappear. Moreover, a high-quality prefabricated house is often even more expensive than a solid house. Some here claim that soundproofing is not a problem in a prefabricated house; I have repeatedly experienced the opposite during viewings. Especially if two separate apartments are to be created, I would pay attention to the best possible soundproofing, and in my opinion, a 20cm thick concrete ceiling simply has advantages over a wooden beam ceiling. The depreciation or valuation by banks and insurance companies has also been extensively discussed. It is simply the case that used prefabricated houses are often valued lower in follow-up financing than solid houses. Likewise, prefabricated houses are assessed lower in value for building insurance (meaning in the event of a claim you get less), yet the premium, i.e., your costs, is the same or even higher. That, for example, water damage in timber frame houses has significantly more serious consequences is also undeniable. In summary, prefabricated houses certainly have their justification under certain conditions; however, especially as a pure investment property, they have not a single significant advantage but rather various disadvantages.