Consider what-condition your-products are likely to arrive in after-shipping?
(bagels ship a lot better than frosted/layered-wedding-cakes ;)
you probably-need a sales-tax/vendor's license from your-county/state-government,
you probably-need some-type of food/health-sanitation license/permit depending on your-state/locale.
Most importantly you need to accept on-line-payments.
Lastly, advertising/web-site-traffic-volume makes a big difference in revenues.