The pricing money-wise is extremely cheap for an MMO. Regarding pricing in Pokédollars it's both server and community-based so there can't be a set price for them.
Also, it really isn't hard to track down people's accounts and chain-ban them (Unsure what PRO uses yet you could easily track accounts through email, IP, MAC address, HWID, ect.) It'd be way more hassle for a player to constantly create new accounts than it would be for mods/GMs to ban them so they're fighting a lost battle.