House Purchase - Complicated Situation

But I would like to pick out one point, or rather consider it more thoroughly than previously illuminated: Where does this desire come from, and is it realistic? - what does it do to the father if you remodel the house differently than he imagined?

The desire comes from both us and my father. He currently lives alone in a house that is far too large, and he himself says that he can no longer take care of everything that needs to be done alone 100%, which in turn leads to the house falling into disrepair. Moving to a one- or two-room apartment (preferably nearby) is completely fine for him.

We might have to coordinate a bit on the remodeling measures, that is correct, but I do not see any major problems here since we have almost the same ideas (new kitchen, new bathroom, etc.).

In general, he has already said that it would be totally okay for him to leave the house completely in our hands and that he will not constantly "interfere."

Has the mother already died or is the father divorced / abandoned by the mother?

I have not yet found out who this father actually is and why only the father is mentioned: has the mother already died or is the father divorced / abandoned by the mother?

A mother (living in a rented apartment) still exists as well; the two are separated. That means each would get half of a possible house sale, which should still be enough for at least a generous down payment on an apartment for my father.

Overall, I would approach it the same way. Perhaps one possibility would be to agree on a market value with the sibling(s). The appraiser also costs a four-figure amount and ultimately only "estimates."

That would be the ideal scenario. Unfortunately, I don't think we can agree amicably on a market value.

One sibling has already suggested that, in his opinion, the future appreciation of the property in the coming years should also be taken into account, which is why he estimates the value closer to 1 million (the location is in a holiday area in southern Germany).

What to make of that remains to be seen...?

Therefore, in my opinion, it is all the more important to obtain a professional appraisal/opinion from a third party about the house value. The only problem would be if the house is really valued at a very high amount. Because then the calculation 600k-400k = 200k no longer works or is financially not feasible for us.

These would be the ideal scenario. Unfortunately, I don’t think we can amicably agree on a market value. One sibling has already suggested that, in his opinion, future appreciation of the property must also be taken into account, which is why he estimates the value closer to 1 million (the location is in a holiday area in southern Germany). What to make of that is another question .... ?

I am actually in favor of, unless the testator explicitly wishes otherwise, a fair distribution among the heirs, but this is ridiculous. Assuming you determine the current value of the property, for that value you then purchase it from your father. Why should your siblings then share in the appreciation of your property? Or does your brother also share in the appreciation of his house? That would be out of the question for me. But precisely because of things like this, it is important to record everything clearly and in detail in writing early on. I would be interested in your brother’s argument as to why, in his opinion, future appreciation should be taken into account?

Because he believes that if the house were only due upon natural inheritance, it would be worth more. So he compares today with some point in the future. What he forgets is that inflation has also devalued his money by then. So the higher amount in the future is still only enough for the house. Therefore, the house is actually not worth more. It at most retains its value. Or rather, the land increases in value a bit and the house decreases in value. So if he discounts the expected inflation again and subtracts the expected maintenance costs, then it can be done that way. But it is a complicated calculation for basically the same result.

I say, ridiculous... ;)

A little less "disparaging" one could say "not fully thought through."