He's got wood- whether it's for caskets or buildings.
Devito is one of the few stable guild directory merchants that carries the wood of the Figmoron tree; a wood that acts as real as any steel to ghosts. Devito also deals in slaves, as well as the arranging of contract killing in Nexus; typically of low-ranking mercenaries and the like. He contracted the players to kill Jarvis Nellens in exchange for the lumber required to arm them against the ghost that possessed Agnes.
He also looks a lot like a less stately Danny Devito.