I assume you're still working on the site and will add graphics and a nice logo, etc.? I don't think $1 is a good price to set. It can be if, indeed, whoever will be selling on your site can sell 10+ items every time they sell it. The thing is, most likely you will be using Paypal for your transactions. Paypal will take their percentage from every buck, leaving your sellers with very little (if they can't sell bulk).