House purchase with unauthorized vestibule

Hello, we are currently in the process of buying an older single-family house that is positioned exactly 3 meters from the property boundary on 3 sides. The purchase process has already progressed, and now the elderly owner has informed us that the windbreak extension (1.5m wide × 2.5m long) is not approved. This extends 1.5m into the 3m boundary to the neighbor with 2 narrow external stairs at the front and back and is the only reasonable way to enter the house. The original entrance now houses the kitchen. Restoring the original condition is not easily possible. Is there a way, possibly through structural modifications to the windbreak itself, to make this entrance situation approvable? Thank you!

If the neighbor cooperates, one could submit a building application with an uncertain outcome. It is best to ask the building authority beforehand. Otherwise, refrain from purchasing.

Addendum: The neighbor has, in turn, built up to 3m close. Therefore, registering a building encumbrance against compensation is not possible.

You only need the neighbor's permission to build within the setback area. Unfortunately, the building authority usually does not look kindly on unauthorized actions. Ask the building authority what you can do there. You can of course suggest to the seller to take care of it before the sale. ;)

To my knowledge, there are "untergeordneten Bauteile" in Bavaria. The distance rules may be violated on at most one third of the length of the construction. This would at least make it permissible.

Does it bother the neighbor? How long has the [Windfang] been there? I wouldn't wake sleeping dogs. If it has been there for several years, it will probably stay that way. There is always a risk.