Escrow Companies and Simultaneous Closings

Can somebody explain to me how the double closing works and how to do it if all 3 parties are out of state? Also, I need a referral to a title company that is investor friendly and experienced. I am closing for a property in FL.

Is this a Simo-Second situation or are you selling in one state and buying in another? Buying two in Florida at once? I have some experience with long distance transactions, (Over-Night Mail, Fax, and an interested party on the other for logistics)