Try out The Elf Shelf at www.schoolpals.net. They let you choose the amount of profit you want plus give additional discounts when your store does well.
We ask for donations from our "crafty" parents (handmade ornaments (we get tons), potholders, candles, soaps) and donations from our "corporate" parents (we have one mom who works for nine west and we get some very nice mommy things). Then we budget $1,000 to be spent on resale items. We buy through Oriental Trading & Rhode Island Novelty and the dollar stores. Our school of 350 made a profit of about $1,500 this year.
You won't make any serious money with a vendor. The last time we used a vendor we made about $300.
My older daughter's school of 500 kids uses a vendor and they are lucky if they make $100. The profit margin is so small. That is why with vendors everyone says it is a service they offer the kids and not a fundraiser as there is no big money to be had unless you do the store yourself.
We have a holdiay shop every year were a handful of volunteers buy the 4000 items for the kids to purchase for their family/friends. It is a lot of work with the shopping, wrapping, getting more volunteers, etc. that we were looking into getting a vendor for next years products. Has anyone gone this route? Is it worth the $$ to get only a % of the profits? We give out scholarships with the money that we earn with the shop and want to make sure that it would be wothwhile to venture with a vendor. If anyone has used a vendor any idea of reputable companies?