Renovate or demolish a semi-detached house - still use the basement

That nowadays it would be different, more generous/opener, does not justify the term "blocked".

You could already make something out of it.

I think asbestos is the least likely issue here. I see a major difficulty for your demolition request in the party wall. Furthermore, I dare to doubt that a new building would be approved here that deviates in character from the other half – I even believe there is no chance for a differing house profile at all.

The stone format used was apparently not yet familiar to the architect; he apparently made mistakes thinking in the octameter system. According to my research, it was not common before 1952, but I estimate the house rather around 1960 +/- 2 years. The rafters have no knee braces, which also contributes to my overall impression. Architecturally, the house could have also fit into the 40s or 50s, but I consider 1932 to be a rumor. For that time, some interior walls would have had different thicknesses; here, apparently, the new Reich format was used for masonry and partly gypsum boards.

A sympathetic house, but very much in need of comprehensive energy renovation; and clearly not suitable for an owner who wants significant changes to the layout. An (additional?) extension could be possible. My tendency is clear: take the appointment as an interesting experience that can’t hurt – but then move on.

An extension would only be worthwhile if it is a good size.

So I draw a conclusion: If you can accept it as it is, that would be okay in itself. Changes are rather not possible.

And I also approached the costs for such a major renovation too high at first.