E-books in auctions

[madfilkentist]

I've been asked to donate a copy of my upcoming e-book to a charity auction. I have strong trust in the auction and the person who asked me, but I'm looking into the best way to do it before saying yes. Does anyone have experience with this, with Smashwords or in general?

One thought is that there might be some equivalent to a musician's download card, though I haven't seen such a thing.