Build a terraced end house with an additional unit (GÜ) on your own

The plot is 141 sqm and at that time was priced at 500€/sqm. That would be about 35,000 for each - with a building obligation within two years.

However, we actually don't want to pay 500 € when you consider that it probably can never be developed or only with great additional costs. A building community is definitely out of the question.

According to the purchase contract, the municipality must take back the plot - however, they certainly won't want to make a loss if they then sell it to us as green space for less than 500 €. The deterioration of the condition is the neighbor's responsibility.

We will see what information we get from the municipality and then decide how to proceed. We actually want to avoid a second terraced house neighbor, except if, for example, our [GÜ] would acquire and develop the plot. Then we could be sure that it would be carried out properly. They are constantly looking for plots anyway. That would then possibly be a plan B.

The most likely scenario is the resale by the community. One must not give oneself any false hopes now. The best for the OP will be a new builder who builds without a basement.

And, if you are already talking to the community, then trigger them at the same time that the current owner must at least restore everything so that your properties and houses do not suffer. Ideally, there would be a double garage there, with each of you on possibly "your half" and set back to the rear as the middle house is planned. This would give you a bit more privacy in the garden and you can leave your boundary development free.

The municipality could have a legal problem with the exemption from the building obligation if other owners in the building area also do not want to build (precedent). Possibilities to circumvent this would be a building obligation for, for example, a garage. Or the parcel is divided and added to the other two parcels (re-survey). I'm curious what the municipality will say...

Oh... the community has deviated from the guidelines set by you in many respects, such as the same roof pitch in the row or that one had not owned property beforehand. Everything was relaxed. And since almost everyone, except for two houses, has already started, the building obligation wouldn't be such a big deal anyway.

Under no circumstances will they forgo the planned revenues, that would immediately become a political issue