It really depends on what you are selling and how much customization you need.

If you are just looking for a basic store front Shopify is awesome. Wife and I have used Shopify and it looks sharp, lots of cool add-ons can be purchased for a monthly fee. It starts at $40 bucks a month.

If you need to code a bunch functionality I can put you in touch with some great guys. Expect to pay $35k if you start from scratch.

I'm happy to chat on the phone if you want details.