House Purchase - Complicated Situation

So first of all, many thanks for the many responses, great that one gets help here so quickly. I will address the posts:

You only get one apartment in decent locations for that. So the 1,000€ is a significantly discounted rent. Thus, your father is essentially gifting you, for example, €60,000 over 10 years. What do the siblings get in compensation for that?

Yes, that is a valid point, we have already talked about it. It would have to be notarized that the siblings receive the same amount at the latest upon inheritance. That is at least my idea so that everyone is as much as possible treated equally...

I conclude from this that a) you have no equity and b) no liquidity. And then you want to buy an apartment to rent out? With €300,000 these are roughly €330,000 (+/-) total costs. The bank will just demand €60,000-100,000 equity from you. Are you aware of that?

Yes, that is clear to us and we are already in contact with a real estate financier. There is equity of about €50,000 available and we have already run through a financing of €550,000 which, with an interest rate of 1.66% and 2% repayment, would be quite feasible given our current income situation.

Hence also the thought that an apartment with €200,000-300,000 is comparatively much easier for us to finance.

You should definitely clarify this beforehand and also discuss it with the siblings. Otherwise, it might lead to disputes in a few years. Even if the siblings themselves agree, but their partners find it annoying (even though they obviously have no say), it can cause tension in the family.

Normally, your siblings would inherit part of the house. If you make a deal with your father, this might no longer apply later on. So they would get nothing because upon your father's death, the house would already belong to you. Maybe a share of the apartment, but that will be significantly smaller.

Of course, it could also be that your siblings already have their own houses and are financially so well off that they don't care at all if you get the house.

Yes, that's right, of course everything must be clarified with the parties involved and also notarized. The first step, however, is to think about HOW this could even be possible, and that's the point I'm at right now.

If you have an idea, just let me know :)

The most interesting and obvious scenario, you named it yourself: You are looking for an alternative, but only you benefit, everyone else is a puppet. Aside from the fact that you want to move into an "unrenovated house"? (or do you want to invest money there), What if you want or have to move elsewhere because of work? What does Dad do with the then empty parental home without rental income? And where do you get your further capital from? Does he have to move again because of you?

The point is that my father wants the house to stay in the family. My two siblings are not an option (own property, etc.). I, on the other hand, am looking exactly for such a property in my hometown and it therefore fits very well that I take it over. Because of that, I am now looking for a way to realize the whole thing while considering all parties, which, as you can see, is relatively challenging. If you have another idea, feel free to share it.

Dad dies and leaves a house that he could still pay off from the rental income of the little sibling. There is then an inheritance community of 3 siblings, of which the one sibling still lives in the house. The house is practically unsellable due to renting and you have been looking at your inheritance for 10 years since the beginning.

What you do not consider is that we buy the house at the official market price. Just not immediately but after a few years. So the entire house value goes to the father (minus any possible gifts which are also considered for the siblings), which he then passes on to the sons again. If we did not move in and my father had to sell the house to third parties, it would come down to the same thing.

Buy the house from the father. He can then buy an apartment with it. Whether he then spends, gives away, etc. the remaining money is up to him. How he inherits the apartment is also up to him.

Does the father leave the house because he
a) wants to anyway (possibly too big, too cumbersome, etc.)?
b) especially because he wants to make room for you?
I do not know the father, but why would he suddenly want to live in a 1-2 room apartment as the homeowner, that sounds odd? In the entire thread, I do not read a single sentence about how the father wants to live. Surely he wants to keep the house in the family, but especially he should have a nice life. If he forgets that, the children should be the ones to remind him or help ensure he does not forget it.
Why not build an extension to the house for the father and essentially create a multi-generational house with assistance/partial care as a notarized agreement? Then the father can stay in the house and be close to his family. We did something like that. We received money and took responsibility in return. Siblings are appropriately considered by notarized arrangements and it can be resolved directly through immediate payment or through a life annuity to the father.

One would simply have to notarize that the siblings receive the same amount at the latest upon the inheritance. At least that's my idea so that everyone is as equal as possible...

And where is the money supposed to come from in the event of inheritance? The house is occupied by you, so selling is out of the question!

What you don't take into account is that we buy the house at the official market price. So the entire value of the house goes to the father, who then passes it on to the sons. If we didn't move in and my father had to sell the house, it would basically come down to the same thing.

???? From what money???
You are talking about money you don't have.
Buying an apartment on credit, making dad move, living in the house yourself as tenants... in the worst case, i.e. upon inheritance, there is an empty rental apartment and a parental home occupied by you.

If you have another idea, feel free to share it anytime.

I already said: there is no plan that is fair to everyone. Everything is very one-sidedly focused on what you want – nowhere is equality to be seen and there will be no such thing on this path.
You are sugarcoating it! But it is not that at all.