Rental house - prefabricated house or "conventional" brick construction

We want to have a house built for renting. Nothing "fancy," 2 apartments stacked (each about 90 sqm), 2 garages,... We are now unsure what makes more sense, a prefab house or a house built in conventional brick construction? Price-wise, there is probably not much difference, we have found out. It should be a turnkey house. Financing is not an issue due to an inheritance, building land is available. Can anyone help us with some food for thought? Unfortunately, we are newcomers to house building and the respective construction companies can say a lot. What do we need to pay attention to?

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.

Thank you Peanuts74 for the detailed and easy to understand answer!

If [Ziegelhaus]... is enough a "residential construction company" (which builds quite a few rental houses around here) – or do I still need an architect?
Sorry for the "stupid" questions, but if you've never built a house before, you first face a wall of fundamental questions....

Finished or prefabricated does not necessarily have to mean wooden panels, and solid does not necessarily mean brick. Aerated concrete is about as common today.

There will always be plenty of pros and cons when it comes to the question of solid or prefabricated houses, and the longer you ask, the more the ratio of comments tends toward 50:50.

Basically, I tend to regard prefabricated house providers nowadays as ordinary contractors to whom you can submit the same preliminary designs for quotation requests as you would to solid construction contractors.

Unfortunately, at present, prefabricated house providers almost all only offer semi-detached houses under the keyword "two-family house" (which can certainly also be placed on an undivided plot, but this is usually a different tenant clientele than for single-floor apartments).

Due to the trend toward individual planning, an old advantage of prefabricated houses (well-developed because it has been built exactly the same way 100 times) has been lost.

Prefabricated house providers mostly build in a fashionably current style, whereas locally based solid construction contractors tend to have everything look the same, even over decades.

a "housing construction company" (that builds quite a few rental buildings around here)

... would be the very last choice for me – if only because they like to build the same style and standard over and over again, so on the rental market you end up with a property hardly distinguishable from what they build for themselves.

or do I actually need an architect after all?

Your own architect is on the client’s side and advises him – a construction drawing submitter in the service of the contractor earns a different bread and sings different songs, but in the end it does not necessarily cost less.

A residential construction company, as you call it, or also a general contractor usually has its own architect who prepares the plans for the building permit. In addition, they often take care of one thing or another related to the construction. In other words, if you know a good general contractor (GU), then you will have less work and stress with the construction.
At the same time, they can usually tell you exactly down to the euro how much you will pay in the end based on the planning (of course, additional costs during the final selection are excluded).
It is important here to carefully study the Bauleistungsbeschreibung (Bauleistungsbeschreibung) and possibly compare it with other offers. For example, what price per m² for tiles is calculated, how many sockets, LAN, TV, etc. are included...
very IMPORTANT, what is not stated in the Bauleistungsbeschreibung is also not included. NEVER rely on verbal commitments here, especially if the contract probably states separately that only written agreements count.
Why build with an architect then? Well, for some it was actually cheaper in the end, although this does not align with the experiences from my circle of acquaintances. However, an architect is often more flexible and may be better able to implement your wishes, while GUs often prefer to build only their 5 standard house types to reduce costs.
However, in the case of a rental property, the question arises whether it has to be the very sophisticated floor plan tailored exactly to your needs, or whether it should be 2 good and reasonably laid out 3 or 4 room apartments.