All prices for art are arbitrary. It's impossible to place a "fair market value" on art. Limited edition runs are just ways to create artificial scarcity. The whole point of photography from the outset is that it's reproducible. Since you're looking to buy "art", you can't look at it as "investment grade". There's no such thing. Everything is subject to fashion and everything falls in and out of favor. Even a Mona Lisa may fetch $10M today only to fetch $5M or $1M tomorrow because it has been "overhyped" or fell out of fashion and its remaining value remains purely historical.
Furthermore, when you're buying art, you're not hiring help and you're not paying for time and materials. You're paying for the feeling, which again, has no intrinsic monetary value. Either you like the work or you don't. If you like it, you buy it for whatever you can afford or you don't buy it because you don't like it enough to spend the asking price for it. That's it. It's as simple as that. Tools don't matter, processes don't matter, limited editions don't matter, the stories behind the image don't matter. Either that piece of work moves you or it doesn't and you decide to buy it or not based on that alone.