He never was a clean person, ever, but now he refusing to wash up. He lives with his son and family, pays room and board. Sometimes it is difficult to be next to him because of the odor. He says he will clean up later, later never comes. He refuses assistance and will not let a paid nursing aide assist him. Would welcome any ideas for this problem. He has accidents regularly.
I'd consider if this person has any other symptoms(refusing to accept that food can spoil, being disagreeable, hoarding items, etc.) and see if they need a medical diagnosis. Sometimes, it's not just being a senior, lazy or set in your ways. It can be part of a larger problem.
Someone should kindly let grandpa know that he doesn't smell fresh. No one wants to walk around knowing they smell. It might be just the thing that gets him back into the shower.
I remember back when one of my Dad's caregivers try to get Dad to take a shower. Dad was pretty shy and kept saying no. Well his caregiver put her hands on her hips and said "Mr. Bob, I raised a houseful of boys, there isn't anything I haven't seen before".... that got Dad laughing and it smooth sailing after that.
As for your Grandpa's clothes, I assume he doesn't run the washing machine himself, so grab those clothes while he is asleep.