Keep in mind why you are involved with your parents. Reminding them . . . and yourself that you are trying to help because you care about them can defuse an emotional situation.
If you have a good history of communication with your parents, ask them what they imagine would happen in certain situations. For example, if they were struggling at home because of health issues, what would they prefer: to stay at home with help, or would they consider other living situations?
Some aging parents may not want to share their financial and legal information with you. If that is the case, at least try to determine if they have a financial advisor or attorney they are working with.
If the direct approach does not work, I recommend a third party. That person could be a life-long friend, a priest or minister, or a golfing partner. It is possible that the perspective of a non-relative helps to bring more objectivity to the process.