Adult trikes usually sell for $200-300 in my area, so anything under $100 is great.
Sun makes moderna adult trikes, but that one looks to be a bit older. I don't think there is any collector value to them.
Buy it cheap and build a chopper trike with the rear end.
Thanks for the info king fish. Actually my moms wanting it so if I decide to get it, it will have some custom work but it wont be to crazy, maybe a repaint with matching tires, chain, pedals and grips