Sketchy careers! How fun. The ones Cheryl mentioned are good. You could always pull a George Costanza and have him be an importer/exporter because, really, who the heck knows what that even means?
My first though for sketchy was he was a mafia guy or hitman so he was really vague about what he did. Or a booky. But that might take your book in a whole direction that you did not want to go, lol.