@HunkyBill: Have you ever made a similar system?
@jesuis.danny: I ve built a sign-up-vendor system for my site: http://19x83.com/account/login
But managing products function is still perfectible. Can't find an easy way to allow my vendors manage their own products by themself. We integrated a product suggestion system using jotforms : http://19x83.com/pages/products-suggestion
Regards,