Buying a house without equity at a relatively young age

What do you think, how did people at 30 save their 200k in equity?

How many have that? Most are still miles away from 200k in equity at 35. Assuming you finish your studies at 25, that’s 40k or 20k per year. Even with interest on savings, that’s only achievable if you earn very above average and at the same time live frugally.

Ultimately, it is futile to argue about which amounts one can personally live on or not. What matters is the flat rate the bank calculates with, and out of self-protection, it will not be based on the lowest standard of living.

Why can’t you live like a student at 23?

Well, probably because then they have a house that somehow needs to be filled and managed. Just that usually leads to “oh, we need something here and something there,” which students don’t do... and from experience, the desire to treat oneself also grows. But basically, I’m often more on the side of “if you really want to, you can try” (if you are aware of the risks) people. But then I might be on “just start trying how it feels.” So if the cold rent is currently 400 euros and in the future the loan costs would be 2k+, just start putting aside the difference (plus ideally an extra buffer for increased ancillary costs) every month. And not in the “oh, something came up this month, so we used that fund” pile, but separately. Stick with that for a few months or a year and suddenly a) you have a much better feeling about whether that’s sustainable and b) your equity pot is already quite a bit bigger. Then of course, possibly this specific house is no longer an option, but I would feel more comfortable with that. Otherwise, I would also just talk to a bank to find out what they think, how much is possible. Basically, it’s a personal decision, but with “young, no children planned,” my question would also be whether it really has to be a house (and the granny flat also initially costs extra). So in the sense that maybe something smaller or an apartment is currently within a more affordable range? Of course, there can be personal reasons why you still want a house, but I just wanted to put that out there.

With two mid-20s master's graduates, I'll go out on a limb and say that properly installing floors is likely to become a real and time-consuming challenge.

And work like interior plastering, doors, or bathrooms is difficult to carry out after moving in, especially not in the granny flat, where the tenant expects a finished apartment.

And if I may return to the "no children planned" thing: for me, no children were planned until my girlfriend became unexpectedly pregnant.
Excluding children in your early/mid-20s and buying a house based on that... that can basically only end badly.

One has to be honest and say that compared to "1 year out of training/studies," salary increases will certainly still come. But how soon these are realistically is something the OP has to assess, as well as how secure the job situation is in general. And the banks will be interested in the status quo, not future prospects. That means even if one is personally willing to take a higher risk (because possibly larger salary increases are foreseeable), it currently definitely has to fall at least into the category "tight but possible" for the bank. And here, some assessments were that this is currently rather not the case (I cannot judge).

I simply find you too young for your own house, especially on credit. Without equity for the incidental purchase costs, my answer is always no. Save up for 2 years. And better look for something without a [Einliegerwohnung].

I just think you are too young for your own house,

You are never too young for a house. It's like the discussion about children. You are never too young for that. Best to start at 18. but today everything is more important than a child. You have to save first, establish yourself professionally, and build a house.

Most children in Germany were born between 1941 and 1945, right in the middle of the war. From today's perspective, the worst possible conditions. The birth rate in the GDR was 4 times higher than in the Federal Republic. And I would guess that the age of parents today is higher than ever.

But I also don't want to pay off my house until I'm 70. So it makes sense to buy at a young age.