“If your parents are getting old and you don't know how to bring up the topic of what to do with all the stuff, I would suggest you pay them a visit, sit down, and ask some of the following questions in a gentle way:

"You have many nice things, have you thought about what you want to do with it all later on?"
"Do you enjoy having all this stuff?"
"Could life be easier and less tiring if we got rid of some of this stuff that you have collected over the years?"
"Is there anything we can do together in a slow way so that there won't be too many things to handle later?”