Thanks! It took a few days, but I did get an e-mail from a helpful human being at Ebay.
Turns out that I don't need to submit any documentation since the funds are going to a large charity. She had some good suggestions and said I can mention in the listing that I've placed a link to donate directly on my about me page. I think that's a great idea, and whether anyone makes a simple donation or not, it will add to confidence. I can link to the official Avon Breast Cancer Crusade page with my name, photo, participant number and pledge total!
Helpful and encouraging. It will probably take me a week or two to get some listings together and up - I'm in the middle of searching out snail mail addresses for fundraising letters and this is all more time consuming than I had realized. Between deskwork and training my son thinks I've taken on a new job. (I guess I have, temporarily.)
I've let it cut into my painting time, and I've got to find a way around that - I'm getting cranky!
Thanks so much, all of you.