When is it considered boundary construction?

Just a question about boundary construction.

If there has been an old solid shed on the property for 20 years, do I have to count it as boundary construction? It was already there before the purchase, after all. And what if it stands about 20 cm over the entire length beyond the boundary? Is that then boundary construction? That is the case with us; the neighbors told us that it stands a little bit on their side, but they have absolutely no problem with it. They then even built their garage against it.

On the other hand, we would now also like to put up a garage. If I have to include the aforementioned shed for boundary construction, can I then ask the neighbors if they would agree if I put up a 9m long garage there? I would then have it notarized at my own expense to ensure it is secure, provided they agree, of course. That way, there would be a public law document with proof that both parties agree.

Is that possible?

Replace "Schuppen" with "garage" and read your report again. Then it should be clear that it counts.

What does the purchase have to do with it?

Otherwise, anyone could bypass these rules with sale/purchase.

In case of doubt, a conversation with the other neighbor helps, because no plaintiff means no judge, and with written consent you can often achieve a lot with relatively little effort at the office even in such cases.

Replace "Schuppen" with "garage" and read your report again. Then it should be clear that it counts.

Why should it then be clear?

What does the purchase have to do with it?

It could be that there are some special regulations, that an old building, constructed before x or whatever, occupies a special status. And maybe you don’t have to count everything or you don’t have to consider this or or or...

Otherwise, anyone could circumvent these rules by selling/buying.

In case of doubt, however, a conversation with the other neighbor helps, because no plaintiff means no judge, and with written consent you can often achieve a lot with relatively little effort at the office even in such cases.

Does that mean (some words don’t really fit) that with written consent you can achieve a lot at the office?

And what about, above all, when the current old shed extends over a property boundary?

And what about, especially if the current old shed extends over a property line?

Does it then not still stand on the boundary or is it so narrow at your place?

Maybe as a small hint. At least for us, there is a maximum length per boundary (9m) and a total length of all boundary structures (I think 15m). Maybe that already solves your problem.