Your post is very interesting, and caused me to do some Googling - and I discovered some of my preconceived notions about reverse mortgages to be untrue. From what I read, it is up to the heirs to sell the house (or keep it by repaying the reverse mortgage principal and interest to the bank). So apparently any selling expenses would be yours. Check out this link. Lots of good info, explained in plain English. Good luck with settling this estate. I'm in the middle of settling my mother's estate, and it's never simple.
Reverse Mortgages: What Happens After Death?