well, you gotta jump into the deep end of high priced corals at some point, haha.
i mean if this piece is not ridiculously overpriced/1 month's rent, and is reasonable for your given pocket book, then go for it! but if you gotta eat top ramen for the next month, maybe reconsider.
blastos are pretty forgiving. assuming you've been keeping your $10 frags alive and growing, then there's no reason you can't do the same for these blastos.
they don't require feeding, but if you can direct feed once in a while, it'll be extra happy with that. and keep your parameters in check and don't nuke it under super bright lighting, things should go fine.
keep in mind that your lighting may be different than the seller's lighting. in which case the coloring may eventually change in your tank. find out what kind of lighting the seller is using. really, find out as much as you can about the seller's tank and growing conditions.
good luck. keep us posted if you win the auction.