I'm guessing your wife's parents are about my age (79). We moved at the end of '23 into a larger home, but we have family living with us, so our arrangement is a bit different. I'm happy to say I helped with the move from the old house a great deal. Although I didn't do heavy lifting, I did paint and got the house ready for sale.

This has been a good experience so far. We make modifications to the new house as needed (for example: stair lift, grab bars in the bathroom). Nothing is forever, but so far this arrangement has worked for us.

Good luck to you wife's parents. May they make friends and enjoy good health in their new home.