Most vendor shops appear to be running Wordpress with a plugin for bitcoin payments. Are there any other opensource options for running a site that will manage order payments?
For established vendors that don't need to advertise on the big markets, and who have high turnover, I think it would be preferable to have their own site to avoid bitcoin theft risk and commissions. But there doesn't appear to be many choices of software available.
This is basically what mail order narcotics was before SR1. Right before SR1 launched, several of them merged into a site called OVDB (open vendor database) which basically was taken over by SR1