Help needed with the general procedure

and my 2 tips in the meantime:
take a look at the [Bebauungsplan] to see what you are actually allowed to build.

and: "turnkey" usually isn’t turnkey. Most construction companies leave out the painting trades as well as the floor coverings in the living and sleeping areas from the [Bauleistungsbeschreibung]. That means: you will have additional costs and another time factor for the completion of the house.
There is a topic here about additional costs (those not listed on the invoice from the construction company) called "Baunebenkosten," unfortunately I don’t have a link at the moment.

Order house catalogs... that way you will know what you don’t want :)

How will the further procedure be? In relation to the property, terms like soil survey and surveying are now floating in my head.

Hello MissFilou,

Soil surveys and surveying can be commissioned by the architect or developer. If it is a newly/recently surveyed property, the boundary markers should still be there and have current coordinate status. If the property has an irregular shape (i.e., several boundary bends and no right angles, etc.), has a steep slope, is to be fully utilized, and/or if the development plan has strict specifications regarding building heights, it is advisable to engage a surveyor early (before planning the house!) and update the planning data accordingly.

Best regards Dirk Grafe

Before acquiring the property, it should be clarified whether
a) there are contaminants in the soil ([Bodengutachten])
b) according to the development plan, or if not available, the neighborhood environment, your desired house can be realized there
As an example: You buy a property contaminated with mercury – then extremely high soil disposal costs will arise.
You are only allowed to build a 100 sqm bungalow on the plot, but you definitely want a townhouse,...
The approximate financing range can always be inquired. In the past, there was a rough rule of thumb: installment up to max. 40-50% of net income. If, for example, €1500 is available, you can currently calculate about €100k per €500 installment per month.