It's all kind of up in the air because SV hasn't come out yet. But I've heard that Blaziken FB Lv. X is going for around 30 bucks, so I'm assuming since it's the most hyped level X, all others will be worth slightly less. Most good holos or good rares, I've seen anywhere from 5-10 dollar per. But I've only checked Ebay once, so... take it with a grain of salt.