Upload & Sell: Off
Here's how I do it...
I create an original in Acrobat Pro (annually) and keep that in DropBox. When I consult a client, I have most of it filled out ahead of time based on email communication, and keep their personal copy in DropBox.
At the time of any physical constult, I open that copy on the iPad and continue to fill out the rest during the interview in PDF Expert. It allows me to get signatures, send flattened copies to the client and retain the original "unflatted" version as well for future corrections and edits.
The same contract can be sent to distant clients to fill out, print, sign, and mail to me. Once I have their physical copy, I sign and scan. They get a copy of the scan.
This system has worked perfectly well for me for two years now.