There is quite a bit of information missing and some confusion. How many homes/mobile homes do you own? It sounds like three in total (your house, a second house, and a mobile home).
The house that you say could sell for $475k...is that what you paid for it, or what it is worth now? If you purchased it 30 years ago for $100k and you could rent it for $2,500 then it might be a good rental. Also how hot is the market? If home prices are still going way up, then it might be worth hanging on to for a while. You might also have to consider capital gains depending on how long you rent it for, how much you purchased it for and what you get when you sell.
Like others have said, more information on the properties would be helpful in giving opinions. You have owned the properties so you should have an idea of what it costs to maintain them, taxes, ect.