Construction costs are currently skyrocketing

[… ] External venetian blinds on all the windows.

I’ll ask openly hypothetically: Who can still afford a new build at 5% interest? In southern Bavaria, where the land alone already costs 350k, it’s probably going to be just as tight as in SA, since construction costs remain the same. So will the rental market tighten due to building stoppages by project developers and private single-family home builders?

That means you either:
a) have the cash and no job that requires at least 50 hours/week.
b) have craftsmen in family/friends who also have time.
c) get a plot of land that doesn't cost as much as the self-built house.
d) can afford interest rates of 3%+ and additionally 3% commitment interest p.a. from the 13th month onward.

As you can see, many ifs. Sounds nice and good, but will rarely be realizable.

I think the land prices will now come under pressure first and foremost - unless it is a premium 1a location (recognized nationwide). Development areas with prices from last year or the year before, which will soon come onto the market, are likely to remain quite empty. Or the price will go down. This has corresponding consequences for the standard land values, and the soon upcoming refinancing of 2013/2014..

It probably won't have any impact that quickly. The financings from that time run at around 3%, so people are staying at that level. And the standard land values were much lower back then than they are going to fall again now.

Well, interest rates of 3%+ existed even earlier, even much higher, and building and buying still took place. The magic word is personal contribution. And of course a reasonably affordable plot of land.