How do you determine a riders experience level?

I have been riding on and off since I was about 6-7 (I'm 21 now). I'm not really sure what level I would be clified as. I have done a TON of trail riding over the years and have some experience dealing with horses being difficult and acting up (and on one who is extremely spooky and will jump 120 degrees at nothing while at a gallop lol). I have a good seat and have never been thrown from a horse. I have done western lessons (when I first started riding), and english lessons (later on), did very well in both. With the english lessons I learned a bit of jumping (she had me doing jumps on my second day because of my prior experience). I have been asked by several experienced riders if I show when they have seen me riding in the arena. Even though I feel fairly confident riding, I'm still not sure what level I would be and what determines that level? I haven't ridden much in the past few years so I'm sure I would have to work a bit to get back to where I was, but I have been looking around at horses to buy and sometimes I find ones that I really like, but the owner says it is for at least an intermediate rider or that the horse can be a bit hot.