#21 - June 3, 2011, 7:04 p.m.
I don't know if a person attempting to corner the market (buying out all enchants and marking them up) would set off alarms for me. You're assuming he made all the enchants himself, which is probably not the case. Market cornering sure is lame, but not a stupid business practice. It's also not a violation of any rules I'm aware of. The amount of items he's selling is irrelevant as there are mods that help automate such processes (and are also not a violation of any rules I'm aware of).
If you actually suspect something foul is going on I'd recommend opening an in-game ticket. But, to me, I'd imagine it's someone just cornering the market, which isn't too uncommon. And being pretty successful at it apparently.