Financing a single-family house with land subdivision - risk or opportunity?

I understood the garages are "under" the ground floor, so basically in the basement/cellar

Yes.

The Stuttgart city council is in favor of the most brutal possible systematic densification. So where there is a will (and preferably no development plan), there is a way...

A development plan exists. But yes, that is the charm of the area.

massive overbuilding even remotely possible?

The development plan says the following: Floor area ratio: 0.6 --> for 335-350 sqm = at least 201 sqm, for 300-315 sqm = at least 180 sqm. That should be ok. Furthermore, the calculation is done according to the "old method," which, according to the consultant, gives us a slight advantage (but here I eventually give up....) Site coverage ratio: 0.4 --> for 335-350 sqm = at least 134 sqm, for 300-315 sqm = at least 120 sqm. Assuming a house of 6.5 m by 12.0 m = 78 sqm. So that should also be ok. I+U (this would allow basement including garage, ground floor, upper floor with knee wall possible)

Eaves height could become a problem. An exemption is aimed for at least partially. The details can of course only be clarified once we have bought or planned.

But please don't forget to also count the garage, terrace, driveway, and the path to the house.

But please don’t forget to also count the garage, terrace, driveway, and the path to the house.

Is the development plan from before 1962? Back then, terraces and ancillary structures were not counted according to § 19.4 of the Land Use Ordinance!

Since then, the driveway and path, garage, garden house, and pool count towards the GFR and may exceed the floor area ratio by an additional 50% in total. Only the terrace is therefore added to the actual floor area ratio.

Hello Schulan,
we are basically in a similar situation, both in terms of income and planning.

Our plot is 260sqm in size. We are planning a construction with an architect with a footprint of 8x10 with ground floor, upper floor and attic + basement. Additionally, 2 bay windows are planned.
In total, we end up with 180sqm living space + approx. 65sqm basement. We are planning 3 children's rooms here (2 already existing) of 15sqm each and the attic is for the parents.

In our region (Rhein-Main) too, the sqm prices are insanely high and building land is practically non-existent, so I can understand your approach. The people who say that 300sqm is too small either live in regions with corresponding prices or are even higher top earners... Ultimately, there is still enough garden space available for sunbathing, barbecuing, etc. One also has to consider that a large garden takes a lot of work and ask oneself whether one would rather use the time for the family (unless one has a huge passion for it).

Ultimately, there is no such thing as too big or too small, but only what fits the personal situation or simply does not fit.

I fully agree with you. The problem is that with smaller plots, more and bigger compromises tend to be necessary, of course depending on the layout. Yes, no one can get a great plot for free, but fitting a "normal" house without major contortions on ~500 m² is generally much easier than on 300 m². In any case, you have chosen the right approach by building with an independent architect (or alternatively with a very good and flexible [GÜ]) to get the maximum out of the plot.

That should be okay.

Might be, but it will be tight since these are gross floor areas and you are aiming for 180m² of living space.

Also, it is calculated according to the "old method," which according to the consultant puts us at a slight advantage

That applies to the base area ratio; for the floor area ratio, it is a disadvantage.

Eaves height could become a problem.

Has it been set? Show more of the development plan.

Is the development plan from before 1962?

The key date is 27.01.1990