Banks here don't care what rent is - they just care what your income is relative to the mortgage payments. My Aspie son isn't likely to have a wife or family anytime in the next decade, I'd imagine - he's only really dated one girl (who turned out to be a bit of a nutcase) and while I certainly hope that he can find love (maybe with someone else slightly on the spectrum) it's likely a ways off. Of course if those things changed I'd probably change my will to reflect the altered circumstances. My Aspie son, though, would always be the one who would take in any sibling without reservation - it's just who he is. I can't say the same of the other two, for varied reasons, that's why he would be my choice to have technical control over the house. (He's also the one who would accommodate CMM in the unlikely event that my death preceded CMM's).