I also think you should consider a few things regarding noise, but the fundamental advantages of the existing property are significant. For example, I NEVER wanted a housing development again, absolutely NO GO.....what do I do? Housing development, but a mini-development and we are at the end of the dead-end street with a view into the wild. As a former resident of BaWü, my house was in the river valley and the S-Bahn ran far away.....of course you could still hear it just like the federal road on the other side. But it really didn’t bother us much, you should really find that out individually for yourselves, I like the idea with the garden chairs or just being there as often as possible to "listen". In my opinion, what can really be annoying is the garden tool battle on Saturday morning or other strange habits of some residents. Recently we lived in the city and what bothered me was this constant buzzing that always came from somewhere else as well as sudden noises like nighttime shouting, slamming doors or speeding cars. I find the train more of a consistent noise that you don’t get startled by and get used to well; therefore, I don’t see it as that negative. I find the thing with the parents to be basically a good solution, without knowing details, especially since it sounds much better than some things that are unwritten and expected for a lifetime and you’re offended if the other person doesn’t do it that way. If I see it correctly, it is a kind of life annuity, so a good and understandable idea, and better that you have payment obligations there than at the bank!