Honestly, the best way to avoid being scammed is to investigate your commissioner JUST prior to commissioning them. Look at their reviews, then come into this section and investigate. Check to see if anyone has had any recent transactions with the commissioner. Even if they had positive reviews six months ago, they could have changed the way they do business. Perhaps they're behind in their commissions for some reason or suddenly stopped responding, but asking around just prior to commissioning them is always the best way to avoid being scammed. I have to thank Axelai and a few other people here for giving me the heads up on the Loserific situation, otherwise I would currently be in the same boat. Her positive reviews are very misleading and while it looks like she's done wonderful work in the past, unfortunately it seems like that quality and work ethic isn't holding true at the present.
AnimeNext Cosplay List
Rapunzel ~ Tangled
Lizzy ~ Kuroshitsuji
I have more, but everything's up in the air at the moment.
Next Cons: AnimeNext, Otakon