He sounds really sweet!
Personally, speaking from "the other side" (as in, I did a similar thing to what you're considering and made the choice to buy), I might hold off.
I say that because, at least in my case, owning my mare fully was not something I was at all prepared to deal with. I thought
I was prepared but once I got in...oh boy. However, I was also 17 at the time...could have influenced that feeling just a bit.
Anyway, owning my mare is probably the best thing that has ever happened in my life to date but it's also the most painful expensive thing that's happened.
I got her sans PPE because I knew her pretty well by the time I paid for her and I thought I knew her issues.
Little did I know that she has an auto-immune disease called ERU (Moon Blindness) that has gradually blinded her. I'm not sure if a PPE would have caught that but it is an unforeseen thing that I never, in a million years, would have seen coming.
She was 23 when I got her and now she's about to turn 28. If she hadn't injured herself in September, we would still be riding the trails together. Hopefully we'll be hitting them again this spring if she's healed satisfactorily.
Basically, the main thing I think you should seriously think about (that I neglected to consider in my excitement over getting my first horse) is that, considering his age, are you prepared to be his last home? Are you prepared to pay the feed bill that will continue to rise as he gets older? Are you prepared to make the hard choice and put him down when his time is up? Are you prepared to never ride him again if his body says it needs that? What if you don't have access to other horses anymore? Are you gonna be ok not riding for months (currently I haven't ridden in 4 months due to Lacey's injury!)? What if you lose your job in a few years?
Those are all worst case scenario things but they are things I wish someone had asked me before I jumped into owning Lacey. I couldn't give her up for the entire world because she IS my world, but I do wish I had thought things through a bit better.
For me, I'm a full time college student with no time for a "real" job so I use Lacey to teach lessons to kids on the weekends. However, that only makes about $40 a week which is just enough to cover her feed bill and $10 of gas for my car each week. Thankfully I still have the option of living at home, but if I didn't I would literally not be surviving right now. As it is, I barely cover the essentials and anything extra takes some real $$ maneuvering. However, Lacey is happy, fed, and safe which is the thing that truly matters so I'm content.
THAT's certainly not something I thought about when I jumped into horse ownership! hahaha
Anyway, just my thoughts.
And yes. The vet will probably charge you to just come out and look. Most vets have a trip fee and most will charge you for a "routine physical" or something similar for a visit like that. I know that when my vet came to check on Lacey after her injury, it was an $112 for the vet to chat with me and make a guess as to what was wrong (of course, I love my vet and gladly pay for her expertise so I'm not bummed or anything). The price will, of course, vary depending on what your vet chooses to charge for his/her various services.