Construction of the passenger car parking space

Dear forum community,

I have a question I would like to ask today.
I have a single-family house, which has now been completed, and according to the building permit includes two parking spaces. These are located perpendicular to the street, at the narrow side of the house. There is a strip of my property about 3-4m wide and 13m long, on which the spaces are to be arranged one behind the other. I hope this is understandable, otherwise I will try to see if I can manage a sketch.
Visually it always looked “level,” but there is actually a slight slope away from the street, so without further measures all rainwater would run to the back and thus onto the neighbor’s property (the same neighbor who borders this strip). The street at the front is the highest point of the strip.
Therefore it is now necessary to adjust/raise the terrain accordingly; it will be supported and filled with L-shaped retaining walls on my property. At the rear end, we will thus be about 70 cm above the previous ground level.

The neighbor was seen over the weekend walking on my property taking photos. He also told my construction workers that they will take everything down anyway and that he will make sure of it. I suspect he will contact the building authority to oppose the construction of the parking spaces.

The building permit contains no details regarding the execution of the parking spaces. The terrain elevation is moderate (see above), and of course I must not drain onto the neighbor’s property — so I have to create a slope in the other direction — and according to my site manager and the head of the civil engineers, such measures are always covered by the building permit. Nevertheless, I am somewhat concerned, admittedly (and of course, I do not want to get into a conflict with the neighbor).

I would appreciate an assessment of the situation. I could certainly call the building authority, but I do not want to wake sleeping dogs either.
If it is important, the federal state is Thuringia.

Dear forum community, I have a question today that I would like to ask. I have a single-family house, which is now completed, and according to the building permit, it includes two parking spaces. These are located perpendicular to the street, at the narrow side of the house. Here there is a roughly 3-4m wide, 13m long strip of my property on which the spaces are to be arranged one behind the other. I hope this is understandable; otherwise, I would have to try to come up with a sketch. Visually, it always looked "flat," but there is now a slight slope away from the street, so without further measures, all rainwater would run to the back and thus onto the neighbor’s property (the same neighbor who also borders the strip). The street in front is the highest point of the strip. Therefore, it is now necessary to adjust/raise the terrain accordingly; it will be supported and filled in on my property with L-blocks. At the rear end, we might reach about 70cm above the previous ground level. The neighbor was spotted over the weekend moving on my property to take photos. He also told my construction workers that they will tear everything down anyway; he will make sure of that. I suspect he will contact the building authority to oppose the construction of the parking spaces there. The building permit contains no details regarding the execution of the parking spaces. The terrain elevation is moderate (see above); I simply must not drain onto the neighbor’s property — so I have to create a slope in the other direction — and according to my site manager and the head of the civil engineers, such measures are always covered by the building permit. Nevertheless, I am somewhat worried, admittedly (and of course, I do not want to get into a conflict with the neighbor). I would be grateful for an assessment of the situation. I could certainly call the building authority but do not want to wake sleeping dogs. If it is important, the federal state is Thuringia.

It is just a guess, but if drainage is done properly and you have observed possible restrictions regarding height and area (these must be in the development plan), then the neighbor cannot do anything to you.

The terrain elevation is moderate

Has the terrain modeling been approved? Formally, you need a building permit for it (at least here in NRW – I speak from bitter experience).

Do you already know the neighbor personally? Introduce yourself to him, have a nice chat as neighbors, and find out what bothers him. After all, you want to have a pleasant coexistence with him later on.

Has the terrain modeling been officially approved? Formally, you need a building permit for that (at least here in NRW - I speak from painful experience).

No, there are no detailed specifications for the execution of the parking spaces, only that two are to be constructed. Building permit according to §34, gap plot...

Do you already know the neighbor personally?
Introduce yourself to him, have a nice little chat as neighbors do, and find out what bothers him. After all, you want to have a pleasant coexistence with him later on.

Well, I bought the house (as a shell) nine months ago. Yes, I know the neighbor personally, and we have had quite a few chats. Mostly, they were about what we are doing wrong (in short: everything!). He is actually a construction worker and knows his stuff. He is well over 80.

He was constantly walking around the construction site, coming into the house without ever announcing himself. He even went upstairs using the construction stairs – extremely dangerous... Once, while I was cutting the floor insulation, he came in. I had just cut myself, the blood was dripping, and I was actually just looking for a plaster... then he gave a lecture about how much I would still regret the underfloor heating. And just recently, when Telekom wanted to connect the house – unfortunately, the nearest pole stands 30 cm on his property – he refused to allow those 30 cm to be excavated because of the loss in value!
Currently, he has put up a fence on the side of his grapevines that border my property, so that I can’t get to the grapes...

I am very interested in a good relationship, I greet him friendly and chat as well, but in several respects it is somewhat difficult with him.