I don't like doing this so I make it worth my time and effort. And it's only friends that ask me to sell for them or friends of friends.
I charge a flat fee of 50% of the total ending price. The shipping cost and all fee's (ebay, Paypal etc) comes out of their percentage also.
I handle it from start to finish. If they don't know anything about the item, I research it for them. I've had several persons bring me items with the pics already done...I'm happy with that. <smile> I pack it and ship it.
We use my Paypal and all the verified information on my eBay account.
Also I always make it clear that my own items for sale went up first, when and if I had time, I would get to their items for sale.
More often than not, most ask me and then when they hear my charge...They'll ask if I'll assist them the ins and outs of how to sell it themselves...which makes me ecstatic!
Once they decide to go it on their own without my doing an offical "consignment selling" they're actually happier.
I always advise Auctiva, Mpire for research and we use my 8 plus years of selling experience to get the best bang for their own eBay fee.
I always get taken out to lunch or dinner as a thanks for helping them to learn, rather than myself doing the whole kit and kaboodle.
I don't sell for others often on eBay as most balk at my 50% charge (which is why I made it high enough to cover my time, my eBay account and more)
I've not run into a single problem since I made the 50% rule and the percentage cuts of how everything works out.
It's best to have that upfront.
Luckily I haven't run into any problems with selling for my friends, but it's because I learned early on to be upfront bout all the charges and to tell them, it's you sell by my rules or I don't do it at all.
My Best,
Donna