I too have older parents. I do not live with them but I understand your dilemma. My father is a hoarder, granted my mother has been able to keep him in check to some degree. I think the solution may be in your approach. I understand that none of you may have the money for a plumber at the moment and you think that putting one of the over the counter "cleaners" in may help. If you father won't go get it, maybe you could and offer to help him fix it. Pick it up at the store for him. I know my once very capable father has lost his confidence in doing simple things. As far as the books go with your mother... maybe express how much other people would appreciate being able to read them and maybe she could find a local group that will trade. That way even if she donates three boxes, she may only bring home a few and not feel like she's lost anything because she will have access to more. I know my parents keep some things because they aren't sure they will be able to get it again. I do agree with the respect aspect as I have had adult children of my own come home. I think my children overstep at times because they are trying to prove that they aren't children anymore and they want to make sure I see them that way. That's not really the issue at all. I can appreciate that my children are grown, but in the same turn I want them to appreciate that I'm doing something that I do not have to do to help them. What I'm saying is just try to make sure your parents know that you appreciate what they do for you and the changes that you want to make are coming from wanting to help them better their lives, not you being a "grown up" and telling them what to do.

Best of luck!