Area in front of the garage according to the development plan

I just checked again, garages are 9m per property boundary

Then you did not finish reading Article 6 BayBo quoted by Escroda.

Art. 6 para. 7 sentence 2 BayBo regulates the already mentioned maximum of 15 meters of boundary development for one property.

By the way, I believe you have already written in this thread that you are planning a workshop. However, the boundary privilege does not apply to such buildings. So you should keep that in mind if you intended to realize a workshop as boundary development.

Then you did not finish reading Article 6 BayBo quoted by Escroda. Art. 6 paragraph 7 sentence 2 BayBo regulates the already mentioned maximum 15-meter border construction for a property. By the way, I believe you have already written in the thread here that you are planning a workshop. However, the border privilege does not apply to such buildings. So you should also keep that in mind if you intended to realize a workshop as a border construction.

Is this also the case for a purely hobby workshop without a lounge area and heating?

pure hobby workshop

Yes, even a hobby workshop is not privileged. That means it may not be built on the property boundary.
The term garage is very narrowly defined.

"Garages are buildings or parts of buildings for parking motor vehicles."
Legal definition from Art. 2 para. 8 sentence 2 Baybo

There are also more than enough administrative court rulings on this.

Yes, even a hobby workshop is not privileged. That means it is not allowed to be built on the property boundary. The concept of a garage is very narrowly defined.

"Garages are buildings or parts of buildings for parking motor vehicles."
Legal definition according to Art. 2 para. 8 sentence 2 Baybo

There are also more than enough administrative court rulings on this.

Ok, thanks for the information. Is there a maximum size for a garage?

Is there a maximum size for a garage?

You can't say that in general, it depends on the individual case (plot size, floor area ratio, development plan, etc.). In any case, you need a building application if the garage is to be larger than 50 sqm and you want to place it on the boundary, Art. 57 para. 1 no. 1 lit. b) BayBO. Otherwise, it can also be up to 100 sqm according to Art. 57 para. 2 no. 1 BayBO if there is a statute. In your case, it would probably be best to get expert advice from a building permit authorized person who can then submit the application accordingly.