you might be getting yourself into some trouble with this one. The big deal breaker is the frame, id have it professionally looked at, and if theres ANY damage to the frame… walk away from that bike! that can be extremely dangerous to ride with a damaged frame. otherwise, if youre getting a hell of a deal on it, it might be worth it. if you do have problems down the line, things can get expensive.
but if your buddy is mechanically good with bikes and he thinks its all good, and there is NO frame damage, go for it.
others on this forum will tell you that the sv650 might be a little too powerful for a first bike. others say its great for a quick learner.
also, since you both know that this bike has seen some ugly days, use that as a bargaining point if you are going to go ahead and buy it.
best of luck!