The e-organizer becomes an app on the clients computer. There is an icon on their desktop. They fill in the data and when they are happy with it, they push a button and it is sent back to the preparer to review. It does not have any means of doing attachments. The client either mails, e-mail (not safe) or uploads to a secure portal the prepare maintains. Alternatively they are given the opportunity to experience LINK.
My suggestion is that you be your first client. Try link to yourself. Send an e-organizer to yourself. See how the product works on the client side, before you send it out to your clients.
Personally, my clients are generally close by, so pickup and delivery is possible. My remote clients don't do technology, so USPS does a bang up job. I do not use link and only have 1 client that seems to LOVE e-organizer.