Property boundary - Building close to it - Permission?

Hello,

friends of mine want to build on a relatively small plot of land. It is supposed to be a house with a granny flat for the parents. However, the plot is so small that they cannot maintain the required minimum distance of 3m to the property boundary.
Who do I have to ask if I want to build closer to the property boundary?

Is a written permission from the neighbor sufficient?
Do I need a permit from the municipality?

Maybe someone knows and can give me a short info.

Thanks!

Regards
Specki

Neighbor, building authority.

Keep money ready ;)

For the approval from the building authority? What is to be expected there?

...
Who do I have to ask if I want to build closer to the property boundary?

Is a written permission from the neighbor enough?
Do I need approval from the municipality?

You or your friend [emoji23]?

Anyway... you don’t do anything at all. You surely know that you basically need a building permit, right? The architect creates the house plan, he also has the overview of what is actually possible. There are quite a few factors like, for example, the neighboring buildings, that play a role. And who knows, maybe you just don't get the 10 x 10 villa on the plot, but the 8 x 12 house will work ;)
In any case, an experienced person has to find the gap and convince the building authority.

How wide/large is the property? You surely have a site plan or something similar?

If the 3m construction boundary cannot even be maintained, then how is the floor area ratio with a granny flat supposed to work?