My opinion of online shopping, is i believe a good idea, the purpose of online shopping originally was meant to be so that the consumer saves, i know that is what u are looking at, which is what we need. Yes I would purchase online if I knew the prices where better, the supplier was reputable, and the products are reliable.
With the advantage of online shopping is that the shop owner/sales person does not have the added overheads like rent, elctricity, if u are running the business from home, the amount of room that you occupy for the business is what gets used for tax purposes. As I learnt all this when i done my business course 6 years ago.
I have a suggestion to the freight/postage costs, though, which could be considered.
As this site has admins,moderators and members from all over the country. Why not find suppliers that deal in most states, such as National Auto Parts, RDA, etc - then assign certain ppl from each state to become a distributor, that way, when a sale comes through for parts, the distributor of that state where the order came from is able to collect the parts and organinse shipping to the customer, therefore saving on postage. It can then also be cheaper for few ppl that live close to the distributor to arrange a pick up.......