Does anyone know of an online service that can act as a "middleman"? Specifically I am buying tax liens from other investors (that I then bring through foreclosure and flip). When another investor and I agree to the transaction, it would be nice if there was a service who I could send the money to for them to hold "in escrow" until the other investor delivers the executed assignment paperwork. I've tried Escrow.com and Shieldpay and neither will do it. Any thoughts?