The oldest won’t get enough money to buy the other two out -1/3 of the retirement savings is equal to 1/3 of the house equity, so he’d have to take out a loan for the rest which would be difficult on his salary, not to mention property taxes and maintenance.
I think some arrangement for him to live in the house for five years if wanted would be enough for everybody to sort themselves out.
Yes, that would work best if you were to pass away now. Hopefully though, none of this will be an issue. Chances are by the time this all comes to fruition all your boys will be middle-aged. I was trying to imagine a middle-aged Aspie who may or may not have a wife/family being obliged to house other middle-aged men with/without families on the passing of their mother. Sounds like the outline for a sitcom to me
I have no idea about the relativities between rent and mortgages, nor how banks work where you are, but I'd have thought most banks would mortgage if the repayments were no more than his rent at the time of application. Property taxes and maintenance are a fact of life. They are paid for one way or another whether you're a tenant (via your rent) or the owner.
Having to be responsible for maintenance is a bit of a nightmare though. I doubt either of my kids would know one end of a hammer or drill from the other. I think I'm going to gift them a Home Handyperson course each for Christmas this year!