> Also, you're going to eventually need to take a very small cut of the donations to pay living expenses for your volunteers. 100% to the patient sounds great, but for my donation, I'd prefer to know that there is someone dedicated full-time to the cause and overseeing the process, and receiving a reasonable salary for it. Of course, be 100% transparent about those salaries as well.

This might also be accomplished with a "tipping" model. Always advertise the full 100%, but when they go to "checkout", give them the option of tipping the organization. Make a default recommendation of, say, 10%, but let them pick their own tip amount as well.

It would be interesting to see what the average tip amount would be here.