They are adults you can't tell them how to do things. But maybe they truly have no idea. You could give them, as a housewarming gift, some books. Maybe a cookbook, an organizing book, a how to clean your house book, a gardening book, a how to book, etc. You could even pay for a housekeeper once a month or something.

Most adults would be offended and tend to do the opposite when they are told what to do. And since you have never lived with either of them they may think you are overstepping your bounds.

__________________
"Parents without the internet should have their children taken away"Peggy Hill
"Well, sometimes when something is funny to everybody, it's really not funny at all." Peggy Hill
"I am a beautiful woman. Hey what are you lookng at? I said beautiful not skinny. I'm not delusional you know" annadrose