Extension to an existing "multi-family house" - boundary distance?

To warm up again here: This project should ideally be supervised by:

[*]Architect [*]Builder [*]??? [*]A mixture of 1, 2, and 3 in varying proportions?

???

Justus Jonas, Peter Shaw and Bob Andrews?

A mixture of 1, 2 and 3 in varying proportions?

If by the Three Investigators you do not mean the aforementioned persons, but a member of my profession, my answer is:
95% 1. and 5% 3. A contractor is supervised by an architect. Although first we need to clarify what you understand by supervision.

I hadn't thought of the audio drama heroes there, rather of further suggestions as to which professional group else could be helpful. Which profession do you belong to? By supervision I meant at least service phases 1-4, since there seem to be various implementations of how much "service" or trouble one would like afterwards. has the opinion here that the person who does the planning should also take on the construction management, but not the construction execution? Did I represent that correctly? That would then argue against a "draftsman's assistant" of a general contractor?

Which profession do you belong to?

Surveying.

That would argue against a "draftsman" of a general contractor?

Definitely. Complex planning law and unclear building regulations indicate an experienced architect. What makes sense after the approval depends on what exactly was planned and how complicated the implementation will be.

Surveying.

The land registry office is commissioned with the subdivision (separation was not possible) and the notary is also there to do his job.

Definitely. Complicated planning law and unclear building regulations argue for an experienced architect. What makes sense after the approval depends on what exactly was planned and how complicated the implementation will be.

So let's see who is considered capable around here

@11ant's opinion here is that the person who does the planning should also take over the construction management, but not the construction execution? Did I reproduce that correctly? That would then argue against a "draftsman" of a general contractor?

I don't think I said it like that. An execution plan follows the design plan, should develop from it, and is therefore in my view always best done by the same planner. The same also applies to construction management: "the conductor being the same person as the composer" guarantees the most faithful interpretation. These three stages therefore belong together. And a construction manager as an employee of the contractor pursues a correspondingly different mandate: indeed also "avoidance of claims" - but from a somewhat different perspective.