Neighbor's garage protrudes 12 cm onto our property

No one dictates the amount of the pension to you. Already to avoid giving a formal point of attack, I would choose this form and agree accordingly with the neighbor.

The suggestion from Domski sounds good. You safeguard your interests (to be safe) and your neighbor should have no problem with it. If I had built over, I would be quite embarrassed.... personally, I would highly appreciate it if you say hey, no stress... I don’t want anything from you and you can continue to use it as before... I just want to officially establish it so that no problems arise for me in the future. Then with a symbolic one euro per year. I mean, what more could your neighbor want? If he then acts stupid, then something is definitely wrong with him anyway.

That's right. And 12 centimeters is really intense, at least by today's standards.

The main purpose of the land consolidation was the adjustment of the cadastre to the existing buildings

I don't know what was carried out with you, but this intention is not covered by the Land Consolidation Act. In development plan areas like in this thread, land consolidation is definitely not an option.

You are (just to be safe) safeguarding your interests

Which ones? He just wants the building overlap to be documented, and that has been done through last year’s survey. If he really wants to be sure, he can ask the neighbor to obtain the survey drawing and give him a copy. At the latest, during the building survey of his own house, he can very easily ask his surveyor to provide him with the survey documents.

I just want to have it officially recorded

It is officially recorded. Probably for many decades already.

Then for a symbolic one euro per year.

Good grief. If you want to make it legally secure, it has to go in the land register.

I mean, what more does your neighbor want?

His peace.

And 12 centimeters is really heavy

yes, 0.78 m². And the OP is building a three-family house. Let's keep things in perspective.

Well, we don't know the overall situation, but such a garage is not standing in a vacuum; it is part of the boundary between two properties. If it now protrudes by an astonishing 12 centimeters onto one's own property, then that has, for example, effects on fence construction and so on. There may then be several offsets. That does not look good. Thus, the problem concerns not only the length of the garage but possibly the entire property boundary. That is then far more than 0.78 square meters.

If it now extends an incredible 12 centimeters onto the own property, then that also has effects on the fence construction and so on.

I don't understand that. Whether the fence starts directly at the corner that protrudes or is set back 12 cm, it doesn't matter. There can't be any further offsets. And what are the effects on "and so on"?

We do not know exactly what it looks like there. There was also no mention of a corner. Therefore, I assume that the entire garage, however long it may be, is offset by 12 cm onto the neighboring property. We do not even know whether the garage is positioned more towards the front or further back. It could be that several meters of fence at the front, if placed on the correct boundary, protrude into the alignment of the garage. Then the garage is offset from this fence axis, and the same situation occurs behind the garage again.