Divide and develop plots themselves

Go to one of the public Bauausschuss meetings and get an impression of how it is composed, what occupies them there, which development goals are discussed, this way you will come significantly closer to an assessment. If you have some liquid discretionary funds and the plots are for sale, just make a move if it is clear that no planning for recreational areas or sealing compensation is intended. Eventually, something always happens in the inner area. The value you pay now will most likely earn you interest back if you build elsewhere in the meantime.

What would be the concrete assistance that one could ask for from these, especially in the first steps of the search?

Well, already the "What is possible?", "How is it possible?", "what is available" (development), a layperson who only knows single-family homes in the form of city villas and gable roof houses, possibly also dormer houses on rectangular plots and terraced houses with their own parcels, simply does not recognize that. The layperson is often already overwhelmed with the HOW part, so that it is fair. A warning: then costs come that no one is willing to pay because at the beginning there is no guarantee yet. So someone has to take the blame. Later on, only half remain because either the right school is not nearby or the area is in the opposite direction to the future grandmother.

Go to one of the public building committee meetings and get an impression of how it is composed [...].

At some point, something always happens in the interior [...]

Thank you!

a layperson [...] simply does not recognize that.

Ok. Am I reading the subtext correctly that one should simply keep an open mind because one probably cannot grasp all the possibilities that a good architect/other professional can conjure out of a seemingly not optimal plot of land? I am particularly interested in the phase before a concrete purchase interest, the grid search for potential plots so to speak.

A warning: Then costs arise that no one is willing to pay because at the beginning there is still no guarantee.
So someone has to take the blame. Later, only half remain because either the right school is not nearby or the area is in the opposite direction to the future grandma.

I hope that one can already sort that out in the course of the search, i.e. before purchase. Of course, the risk remains.

Up to two full earners each (according to the status of family planning) with solid equity.

So all with about 40-70% financing. No one who would not be ruined by fronting a six-figure sum.

Irrelevant for the approval of subdivision, construction projects, etc.?

Yes. The actual use in the cadastre or land register has no direct building law relevance. However, it serves statistical purposes, for example to justify a planning requirement (land use plan amendment, development plan preparation).

What concrete assistance could be asked from them especially in the first steps of the search?

An initial assessment of the planning law situation of a possibly suitable plot of land. Here are three examples from a randomly selected village in the mentioned region without checking the actual conditions:
[ATTACH alt="beispiel1.png" type="full"]64330[/ATTACH]
Parcels 729, 730; unplanned inner area; buildable according to §34 of the Federal Building Code with 6 semi-detached houses.
[ATTACH alt="beispiel2.png" type="full"]64332[/ATTACH]
Parcels 65-69 and possibly parts of neighbor plots; possibly §34 Federal Building Code (see above), possibly outer area within inner area according to §35 Federal Building Code, which requires the establishment of a development plan possibly according to §§11ff Federal Building Code, which requires a lot of experience and advance payment.
[ATTACH alt="beispiel3.png" type="full"]64333[/ATTACH]
Part of parcel 701; a development plan is certainly required.

I assume the matter is basically settled (or at least no longer advisable) with unwilling local politicians?

Yes.

What importance does the rest have?

Hard to predict. However, in the Rhenish lignite mining area there is a high sensitivity to interventions in nature.

Is there a reasonable approach to exclude the presence of rare animals and plants in advance with comparatively high certainty?

Yes, there are various experts for this.
But honestly: This is for people who want to avoid negative interest rates. As soon as you have to create the planning law prerequisites by establishing a development plan, the risk simply becomes too great. Look out for plots of category 1.

Thank you very much for the hints and examples, these are extremely helpful!

I have one more question regarding example 2: When/how can I most easily find out whether parcels are "Außenbereich im Innenbereich" (great term!)? According to the land use plan of Bergheim, parcels 65-69 are residential building areas, is that relevant, or does it always only help to send an inquiry/make a call to the responsible office - and which would that be for this specific question, building authority?

Otherwise, based on previous answers as well, I roughly read the following:
- Stay away from the Außenbereich, even if inside
- If inside, have a professional check whether/how a potentially suitable plot can be built on according to §34 of the Building Code, otherwise stay away. Do not underestimate what could potentially be suitable, because a trained eye recognizes much more than a layperson.

Is that roughly correct?

When/how can I most easily find out whether parcels are "outer area within inner area" (great term!)?

Legally binding only with a building inquiry. I have experienced that one and the same caseworker came to a different assessment for the same plot after two years without any changes to the conditions. Unlike me, he had not documented his first statement.

According to the land use plan of Bergheim, parcels 65-69 are residential building areas, does that have relevance?

For your project, yes; for the inner/outer boundary it is an indication, a puzzle piece. Whether the urban structure allows development without a development plan depends on many individual factors, e.g. the municipality’s land balance.

or is it always just a query/call to the responsible authority that helps?

Not always. I doubt that an informal inquiry will yield a meaningful answer, certainly not a call.

and which one would that be for this specific question

That depends on the organizational structure of the municipality.

Building authority?

Does that still exist nowadays? Today there are specialist departments and managements. I think the city planners have to comment on this, whatever their organizational unit is called – it used to be the planning office (A61).

- Keep away from outer areas, even inner ones

Not necessarily. Although I strongly advise against developing your own development plan, in June the extension of §13b of the Building Code was passed, which makes it easier for municipalities to establish development plans under certain conditions. With a bit of luck, a group of prospective builders might find open ears.