Depends if you want a project or not.
If you want a buggy, tell the owner to sell it with a RWC. It'll cost you, but it'll save you lots of hassle.
If you want a project, yes, check the paperwork, and put it in your name, without a RWC. It's fine, you just don't get a disk so you can't drive the car until you RW it. Then you look at the condition of the buggy.
1) Pan
2) Wiring
3) Suspension and brakes incl hand brake
4) Check if it runs... if it does, take it for a spin.
Oil leaks? You can count them if you want... If you get a buggy without an oil leak, check the oil...
