sounds like some sort of money laundering scheme. he needs to "clean his money" and what a better unsuspected place than reptiles. he sends you 1900, you send him back 1700 and a snake.
he then either sells the snake, or disposes of it (expendible asset)
his money is clean, since he has the proof that he sent you 1900 and it was cashed, while he gets 1700 and nothing saying it was ever "dirty money". for all the authorities know it could be an inheritance or something.
either way, it does smell fishier than a new york fish market, and that's pretty damn fishy.
"I scrub and I scrub and yet I still smell...fish!"
or I just read into things too much.
