Your passport is your freedom. Pay the 5000 baht deposit. You can not leave Thailand without your passport. Most places take deposits. I rent bikes to get my passport stamped so I cant leave it for them. I give them a photo copy and a deposit. I saw a drunk farang give his scooter gas when he was not on it lol. It went flying into a tuktuk. They are concerned for a good reason here. I can talk them down to 250 baht a day. I don't recommend any because they all seem to treat you like you are here for 3 days..
I use moneygram. You get going rate for flat fee. My fee is $2.50 canadian per transaction for money pick up. I just go online and send the money to myself. I just make sure the pick up spot has the cash on hand.