Have $200 cash to send in mail
Looking to buy your BTC for USD cash
I only deal using an escrow at your expense.
Post your rates here
You are planning to post $200 and expecting the other party to have an escrow when you are going to POST money to them? That is the most untrustworthy to send things like money because thre is so many chances of interception along the way. I would suggest you use a more stable method such as bank transfer or at least insure your delivery of the money.
There are plenty of people who have done exchanges like that; IIRC, Quickseller once used that sort of exchange with another member. Interception chances are actually pretty low, I imagine, since mail has a 99.999% chance of being delivered successfully and there aren't many places where mailmen regularly tear open boxes and inspect its contents to steal it.