I am sure many others will come after me and elaborate on this. But I can tell you that if this is your first airplane you will crash your corsair on your first flight, unless you have help. First thing to do is find a model club and an instructer. The instructer will most likely have a favorate trainer plane. You should buy a good trainer plane (I like the nexstar, just take off the AFS) and learn to fly it first with the instructer. Then get a good second plane (Such as the Sig Four-Star). And then after getting comfortable on it, if you are a natural, like myself, you may be able to move to the corsair. If you are not really good I would get a third plane, then fly the corsair as a fourth plane.
Karter

EDIT: gosh in the time it took me to type my post two other people posted. I agree with kwigen, be wary of used four strokes. And they are harder for newbs to run (I would know, I am one) So start with other planes and move to the corsair. Who knows? maybe you will be able to do four stokes good by the time you fly the corsair.