Honestly, I don’t understand the problem behind your question. If you allow yourselves a "Yes!" to the question "Can it be a little more?" not only at the sausage counter (for 270 g instead of half a pound) but also in the real estate market (for 600 instead of 400 sqm of building land) and can afford to develop that with at least the assumption of 3k per sqm with 190 sqm living space plus a granny flat, then you apparently only know money problems from TV. In that case, you wouldn’t have the slightest concern about whether and to what extent building will become more expensive. Even being able to afford 600 sqm of land speaks for solid finances and/or that the Stuttgart metropolitan area is defined very broadly and we are not talking about Rutesheim or Ditzingen, but at best about the "Greater Leinfelden Area" (?)
We are also wondering whether we should actually start building the house immediately or better wait another year and see how prices develop. Currently, we live in a paid-off owner-occupied home in town (which is permanently too small for us, so we will sell the duplex and build a single-family home) and have three years after acquiring the land to start building the house. What is your assessment regarding price development?
Just imagine the time back: five years ago (= before Corona), ten years or more (before Lothar, before Kyrill, ...). Since then, construction loan interest rates have sometimes fallen, but construction and other prices have also risen. These are not events that occur as rarely as Halley’s comet. Suppose Putin / Hamas or the like were history next year and Habeck’s “heating ban” as well, chip shortages or delivery difficulties for heat pumps no longer existed (there are still people who believe a good fairy is born every morning). There are reasons why I called my info blog "Building now," because no luck for the hesitant is in sight. Betting on falling prices is for fools who want to become poorer (in terms of purchasing power). Time does not heal prices. Even Kostolany would never have gotten rich by waiting if the thread of crises had once broken.
I would be very happy to get tips from you experienced people on how we should proceed with the construction cost estimate. For example, go to local construction companies with our wishes and simultaneously inquire with prefab house manufacturers, or better consult an architect?
There is no "or" before an architect here. Construction companies and prefab home providers like to advertise that you don’t have to pay extra for architectural services, but they expressly refer to "necessary" architectural services, i.e., those required to obtain a building permit. And of course, they let customers move the windows around the facade until everything looks balanced for symmetry fanatics, or draw several appearance simulations for them. Nevertheless, I recommend
never going to a general contractor instead of an architectural planning and tendering (regardless of whether masonry or "wood").
As someone currently also professionally a construction consultant and overall with four decades of experience in owner-occupied home planning, I can assure you that every saved architect fee can be transferred 1:1 to the cost item "surprises," and the large fee portion for service phase 5 in particular pays off fully. In service phases 6 and 7, it is even the case that building without proper tendering will be more expensive (the only exception: with employee discounts at the building material dealer, you can compensate so far that you effectively end up with zero savings).
If you now go "unprotected" through an architect to a construction company (as said, regardless of the building method), they can name prices for you. But these must be treated with the same caution as those estimated by an expert at the current planning stage. They will give you prices for (including the granny flat) 220 sqm that would make you think the warners are all pessimistic doom-mongers and building is actually cheaper than thought. But even without future price increases, it would only fit in the end if you finance and trim painfully.
We are open to both solid construction and prefab houses.
That’s very good – as well as that you want to select the masonry builders from the region. They are usually more recommendable and won’t beat you down with their legal departments like the big names with their fancy brochures in case of complaints.
Thank you for the note. We actually already know very precisely what we want. Have written everything down and are currently having it drawn.
Who have you chosen for this drawing? Freelance architects (mostly at the cand.arch. stage) are a suitable address, less so draftsmen. It’s already very good not to have concocted an amateur plan yourself. But you better go to the architect afterwards, despite the drawing, at first only with the requirement and wish list.
Since we are both busy professionally and have children, we are not planning any own labor.
That is a very important point. That rules out all self-builders (Allkauf Haus, Massa Haus etc.) already, and actually also turnkey discounters like Scanhaus Marlow & Co.
Resist the fallacy that a general contractor is "the solution"!
I recommend the following approach:
1. Read the existing threads here with the forum search terms like "housebuilding schedule," "Gerddieter," "individual awarding"/"own awarding" concerning the procedure for house planning;
2. now visit construction companies and model home exhibitions. Choose providers for higher demands with caution (you will need the buffer) and consider stalking by salespeople, i.e., create a disposable email address and a prepaid dumb phone;
3. go to financing advisors and also get a building plot appraisal;
4. commission a freelance architect with service phases 1 and 2 ("Module A" see "A house building schedule, also for you: the HOAI phase model!" - external, so search with quotes);
5. during the dough rising phase, go again – now with the architect’s preliminary draft – to construction companies and house manufacturers (this time in the actually suitable market segment), meanwhile you or the architect submit the building preliminary request;
6. derive from the feedback of your price inquiry a decision whether to plan service phase 3 (design) in masonry or wood and commission the architect for the further process (see contributions on the above-mentioned keywords).