If that is in dollars, he's nicely priced, about £5,000 I think, which seems about right for a horse of his age and type. (verging on expensive but that's just because the market here is shot at the moment) However if you just want to learn english, would a loan not be better until you have the hang of it? (and lucky you, having an indoor arena!!
He is a nice looking chap, my kind of horse, and if you want quiet you are better going for one of that age. If he's been a child's mount he won't have been jumping very big, and the jumps in the photos are only little so hopefully he won't have been worked into the ground
There's a horse down the road, an RIDx, that is 28, he hunted until he was 22, so not exactly a quiet life, and is now a childs horse, still jumps, does shows/rallies etc, trust me, a 16 year old has a lot of life in him yet!
I must admit I do like him a lot!
There are two things that trouble me, the first is that he has a lot of muscle under his neck, which makes me think he hasn't been worked properly (if at all!) for a while at least.
The second is, why the dodgy clip? If he's difficult to clip I doubt he is a genuinely quiet horse...
There are not many 16 year olds that would pass a full vetting, but if you decide to proceed I would recommend you get him vetted so that you know what you are getting into!