House purchase from hesitant neighbor

What exactly would you want to renovate while the person is still living there?
You have to keep in mind that the tenant always has to help out a bit. Even if it is "just" moving furniture / items aside so that the craftsmen can work. And it basically doesn’t matter how neatly the work is done, you still have to do a little cleaning in the end. Who is going to do that?
Someone over 80 is usually significantly less flexible and less spontaneous than we are. So if they don’t feel like dealing with the disturbances caused by the craftsmen, they simply don’t open the door and that’s that. I have also experienced this in my circle of acquaintances.

I find it a logical, but rather selfish thought to "secure" the house for yourself. Then the tenant has to endure renovation work so you can potentially save x thousand euros? Apparently, you have enough money to buy a second house. Then it would be decent not to (only) see your own advantage.

Then the renovation will just cost 50 thousand more later. That can be planned for now.

Honestly, I even believe that your impression of decay can be a self-reinforcing perception. If not half the roof is uncovered or the house is tilting like the Leaning Tower of Pisa, you can't say much about the building condition without closer inspections. Moisture in the basement was normal back then and is not automatically a defect.
Flaking plaster or paint chipping off the windows. Yes, that will cause costs later, but it is not automatically a huge problem.

Thank you for your answers. The topic was amusingly clarified today during an almost one-and-a-half-hour garden fence chat. We agreed on the essential idea. He will discuss it again with his son, and if there are no objections from there, we can calmly deal with the details.

For the "only see one's own advantage" faction: that is precisely not the intention, as described. ;) He was very pleased today that I brought it up again and would think it’s great if someone is willing to continue to take care of the house. :) Especially with the damp basement, he has realized that it is getting out of hand for him. Back then, he invested a lot of personal effort into the house with his parents and would be happy if the house gets a new perspective. :cool:

First of all, good, yes.
You still shouldn't get euphoric. Yes, he wants to see the house in good hands and is happy about a renovation.
But that by no means means that he will be enthusiastic once it starts and you might want to change a few rooms right away... Houses from the 50s generally don’t fit today's ideas in terms of room layout and size...

So it can very well be that a switch is flipped as soon as the first craftsman swings the sledgehammer and then he no longer wants it...
It doesn’t have to be, but you have to be prepared for it.

And you are exactly facing the decision:
Being selfish and carrying out the renovation even though it makes the old man unhappy... after all, it’s your house now, no longer his...
Or calling back the craftsmen...

I would really be very surprised if he lets you renovate his parental home according to your ideas and sits happily smiling beside it.
Especially since at his old age it is also a big burden to live on a construction site for months... if that’s even possible.

With a renovation you usually do water, sanitary, and electrical work at the same time, right? He can’t live there during that time... will you provide him with an alternative apartment including the move?
Or is his son supposed to accommodate him free of charge then?

I think you haven’t considered many “little things” (yet). You have to be careful not to promise anything you can’t keep.

everything beyond emergency repairs is wasted money. If someone from the family wants to move in, it will be completely renovated anyway. then it does not matter whether the windows were painted (new ones will come in anyway) or the plaster is flaking off (insulation will be added) etc. The only thing that might come up for you is the heating, which has to be done in the event of a change of ownership. I can understand, however, that one wants to check who lives in the neighborhood.