Could someone Help me answer this question

[Richard Armendariz]

My Q: My father owns his house clear and Free, about a year ago he open up reverse mortgage.He asked me about a six months, if I would like to buy from him for $150,000. It's worth around $475,000.My mom and dad both live in this house, both ages are 76years old, in good health.I don't have the $150,000.But what I was thinking of doing, giving them $25,000, down and make their payment the Reverse Mortgage, is paying them.They will still live in this house till they pass. Has anyone done this before? Does anyone have any other Ideas? I live in California.