Carport vs. Building Boundary - Lower Saxony

With us (also Lower Saxony) there was also a "need for discussion". But everything was clarified. We had an appointment with the manager and then everything was fine. With such "inquiries" from employees, there can always be communication problems (wrong explanation of the situation, etc.). Just ask for an appointment; take the plans with you - the boss there has to explain to you why it is not permissible.

I am not legally certain. Surely, I would not build the carport without a building permit now if I were in your place. You also have a "larger" option with a building permit.
Therefore, I would actually have an architect or someone apply for it. Professionally competent, they can also include the connection to the neighbors' carport (you are building onto it, right?) in the plans or represent it.
I would ignore the previous negative statements from the building authority and attribute them to Corona-related confusion.

Hello and thanks again!
No, we wouldn’t build the carport now "into the blue" without a permit anyway – especially since with the informal inquiry at the building authority (which, by the way, was made recently and not during Corona high times) we probably woke sleeping dogs anyway...
One more note about our neighbors: their carport is actually on the other side of their house and thus does not border our property – but it is still affected by the same rear building boundary. For your information, I have attached some photos again that show the current parking spaces (to be roofed with the carport) and the surroundings.

Best regards
Beiunszuhause

Building without permission is completely legal. You just have to comply with the legal regulations.

But if you want to build 6*6 m, then you cannot avoid a building application. I consider the approval to be a mere formality.

I will quote some basics:

"Which documents are required?
For vehicle shelters that require approval, you usually have to submit the following documents. If in doubt, ask the building authority of your municipality or city.

[*]Structural calculations
[*]Building description
[*]Construction drawings from three views
[*]The estimated costs for the construction
[*]A simple site plan with overview map
[*]The carefully and fully completed building application, available at the municipality, the building authority, or on the internet
[*]The construction project must comply with the development plan

Tip: Manufacturers of carports often provide you with some of these documents.

What fees apply?
Within the rules, erection is free of charge. For an approval, you will learn the exact costs from your building authority.

What deadlines must I observe?
In any case, find out before building the carport what is allowed in your municipality. Building without a building permit is prohibited in Lower Saxony and punishable."

I also have a question about this topic. I have read the guidelines, but I don't quite understand them: We have purchased a property, a single-family house with an existing garage and garage yard. At the corner of our property, I want to build a carport. It borders two neighboring properties and our garage yard. Am I allowed to put a small carport there (2.5 meters wide and 5 meters long)? see professional sketch, red carport, blue our property

There is quite a large tree standing there. Is it allowed to be removed? I imagine the driveway to be a bit difficult. Or are you allowed to drive over the neighbor's driveway?

I have read the guidelines,

Which federal state? In general, a total of 15 meters of boundary construction applies. The garage stock has 3 meters and 6 meters respectively as boundary construction? Then you should still be allowed to build 6 meters at the boundary. Theoretically, the carport, as you have drawn it, must maintain a distance of 3 meters at the back. However, it would need to be clarified whether you are allowed to build on the path (it's a driveway, right?).