That's a nice plan but there's a big problem you overlooked. PayPal is reversible up to 180 days and that red trust is difficult to ignore.

Escrow can't protect the person you send PayPal to. That's because of this reversibility issue. When you get the coins, you can immediately dispute the payment or even charge it back if the source of those $900 was originally a credit  card linked or a credit card transaction paid into your PayPal account.

You have other options.. trade your PayPal funds with a friend or family for cash, then use that cash to buy coins here using a less reversible method of payment. Or withdraw the money from PayPal into your bank account, then withdraw the cash and pay using a safer payment method.