Land in sight, is house construction financially possible?

That is a lot of money regarding construction supervision and the like. Who exactly does something like that? Are you building solidly with individual contracts for the trades or also timber frame prefabricated construction with a general contractor? I wonder if the latter would be cheaper.

Good planning and construction supervision "cost" nothing insofar as they pay off. Here you will find, using the search terms Hausbau-Fahrplan and Gerddieter, posts in which I explain why the decision between Holzer or Steiner should not be made before the Teigruhe, between Modul A and Leistungsphase 3; and with the search terms Eigenvergabe, Einzelvergabe, Ausschreibung and Regiestunden, those in which I address the icebergs on the high seas of backfiring "stinginess". "General contractor after tender" is often not a bad way, while "general contractor instead of tender" is almost always, and very decisively so.

I just did it: BLV is depending on deductible 77 ct (500 EUR deductible) or 82 ct (250 EUR deductible) per 1,000 EUR construction sum with Gothaer in my case and builders liability insurance once about 325 EUR with DEVK.

Regarding the topic QNG: What exactly do you want to do yourself again? That is extremely dangerous! The limit values occasionally increase and with QNG you only have to use the wrong silicone for your own work and it can ruin your values during the air measurement... My energy consultant has advised against calculating with QNG for any own work... Whether he is right I cannot judge, because I am not a professional. I just want to tell you: Be sure to be careful! Especially with the costs for the calculations from the energy consultant, what is included and what still comes extra after the building acceptance for the BnD certificate and the tests for it...

That sounds really serious. Basically, the calculation of the house turnkey = everything complete including doors, floors and walls. I had considered whether we might do the latter ourselves, but after what you write I am worried. But interior doors, floors and walls would not change the energy balance of the house, would they?
In addition, we would have taken over the garden and paving ourselves.. I consider that manageable with the small plot.
But if anything endangers QNG, I would not touch it and recalculate. Without 190k for the low interest rate, I would only very reluctantly want to start the house building project..

A good planning and construction supervision “costs” nothing insofar as it pays off. You can find here with the search terms Hausbau-Fahrplan and Gerddieter the posts in which I explain why one should not make the decision whether Holzer or Steiner before the Teigruhe between Modul A and Leistungsphase 3; and with the search terms Eigenvergabe, Einzelvergabe, Ausschreibung and Regiestunden those in which I address the icebergs on the high seas of backfiring “saving foxiness.” “GU after tender” is often not a bad way, “GU instead of tender” however almost always, and very straightly on target.

That sounds so profound that I do not understand anything until I have searched for Gerddieter and Hausbau-Fahrplan. If there is anything in there that I should know very, very urgently at this point – please – gladly translate it for me!

But interior doors, floors, and walls wouldn't be able to change the energy balance of the house, would they?

I am not familiar with the topic, as we distanced ourselves from the QNG concept right after the first sentences about it from the energy consultant... These sentences included, among other things, that all materials used in the construction of the house require a sustainability certification, and afterward, for example, an air measurement for pollutants must be conducted during acceptance. That was then the issue with the wrong silicone, which can exclude you from the funding requirements for the loan after the completion of construction.

How the whole thing is handled in practice and what the exact requirements are, I cannot assess. My advice at this point would definitely be to consult your own (!) energy consultant specialized in QNG (not everyone can do this) on an hourly basis in advance to discuss everything specifically related to your project. I said at the beginning that I just want to raise awareness here that QNG is probably not a walk in the park and has many (also unknown) pitfalls.

I definitely don’t want to demotivate you or anything—just warn you that you should definitely deal with QNG more thoroughly beforehand... :)

The small component (in your case probably 140,000 EUR?) is much easier to achieve and it only concerns the energy balance. You can also do a lot yourself and are on the safe side once it is calculated exactly what is being installed. But according to your list, all the necessary work for this is being done anyway by Hanse Haus... Wouldn’t that be an option for you?

Thanks, also very helpful info. That is a lot of money regarding construction supervision and co. Who exactly does something like that? Are you building solid with individual contracts for the trades or also timber frame prefabricated construction with a general contractor? I wonder if the latter would be cheaper.

I haven't decided yet. Since I also want to take advantage of the QNG funding and have an absolutely unproblematic plot, I am leaning towards a timber prefabricated builder, but for completeness, I will also inquire with the local solid construction contractors with my plan and equipment list.

Construction supervision you just have to look at the fee rates for contract review architect/contractor, foundation slab inspection, shell construction inspection, final inspection, etc. Nice sums add up if no problems are found.

since I have an absolutely unpretentious plot of land, I tend to go for a prefabricated wooden house

I don't see the connection.