Building housing on existing land ownership - ideas wanted

I would definitely first ask whether on 1 a detached single-family house would be possible with access via Reiterweg.

I wanted to approach the municipality with something more concrete first.

Why? They don't bite and are exactly the ones responsible for such questions.

They don’t bite and are exactly responsible for such questions.

A building preliminary inquiry (or the equivalent concerning a change of use) can resolve the question definitively. Unfortunately, a "voting result" of a forum poll has no legal effect, i.e. you can’t "rely" on it ;-)