Is this just a one time thing--or is this around a business where it is going to be happening all the time?

By processor I mean a credit card processor like Paymentech or Verisign or Cybersource. Paypal offers most processing and bank functions, but you pay for it and are forced into their API. Most of the major processors now have eCheck products, though I haven't used them and am not sure on the pricing, but it should be less than credit cards.

On the backend (you sending the one payment) I meant just doing an electronic bill pay from your bank account where they send out a paper check. This is usually free for you on a small enough scale. And it would further extend the float period.