Adjacent neighboring garage (existing building) with a height of 3.6m

I have now called another building authority and explained the situation. The gentleman said (of course with all disclaimers, as he does not know the development plan and it is not his property), that the neighbor’s garage height is not relevant to my building project, as long as there is no registered easement on my parcel or the development plan specifies otherwise. An "additional" setback area can only be triggered by an easement. When examining the development plan, they only look at the configuration on my property (development plan, state building code, possibly easements). ->As known, there is no easement here.

Since the property is already purchased, I cannot do anything about a potentially too high neighboring garage if the "solar theft" bothers me. The property is bought as seen. He also said that the wall height measured today can easily be over 3m. The reference is decisive. It is quite possible that the nearest street centerline is about 1m higher than the current ground surface. That apparently is not uncommon.

Clarity would be provided by a preliminary building inquiry or a building application.

It was definitely very interesting.
Attached I have marked the map with the buildings for you.

You mean, although the state building code is violated by the issuance of the building permit, it is still granted? I wouldn't be so sure. You?

I don't see anything violated or endangered here at all, and after all, no intern handles this at the building authority.

I called another building authority and described the situation. The gentleman said [...], that the neighbor's garage height is not relevant to my construction project, as long as there is no building encumbrance on my parcel or the development plan stipulates otherwise. An "additional" setback area can only be triggered by a building encumbrance. [...] Clarity would be provided by a building inquiry or a building application.

I already said all that. And also this:

When examining the development plan, they only look at the situation on my property (development plan, state building code, possibly building encumbrances). -> As is known, there is no building encumbrance here. [...] He also said that the wall height measured today can well be over 3 m. The reference is decisive. It could well be that the nearest street centerline is about 1 m higher than the current ground surface. This apparently happens quite often.

First of all: I have no experience with such a case and no legal knowledge in this regard. Personally, I would not make a fuss about it at all, I would just submit a building application and that's it. You are not obliged to measure the neighboring building or to tell the authorities that you noticed that... In our building authority, nobody comes out to measure or check with a regular building application, unless you apply for exemptions from the development plan. Then they might look at the situation on site and then something right on the boundary could of course be noticed.