is not a layman and is therefore right?!
Correct, he is a certified surveyor.
Without intending to offend Dirk, he has a different perspective on the connections between the property and the existing building than, for example, a salesperson who deals with these matters daily. What do you think is the reason I have been repeatedly advising you (by now) to involve an expert?
Of course, the building is still under warranty, and this also transfers to the new buyer. But – who supervised and accompanied the construction of the house? Who carried out the acceptance(s)? And ... and ... and? There are many question marks, as you rightly recognized, which
only an on-site inspection with expertise can answer. Everything else is groping in the dark, and I have been doing the job long enough by now.
Rhenish greetings