I would like to open up an ecommerce shop but not only sell my items but strike a relationship with other retailers and sell there items as well.
With this idea brings problems, do you know of a php ecommerce package which can cope with order fulfilment and automatically send an email to the relevant supplier and also allow for order tracking i.e. they would update an extranet or similar to the progress of the order.
Any help would be most appreciated.
ZenCart can do all that for one user. I'm sure that with some modifications, you could do all that for many users.
A simple way to do the email thing, would be to have all the emails drop off into one inbox, like firstname.lastname@example.org then using filters, forward the notes to the appropriate supplier.
When payment is made which merchant account is used, yours or each individual retailer partners? If you are going to use your own account for credit card processing then it sounds like you want to be a drop-shipper and you will need a modification to track products by distributor and send them the appropriate order info (each order could have products from multiple retailers.
If you want each retailer to provide their own merchant account info for the sale then you can't have a customer purchase from multiple retailers since they would have to pay multiple retailers. In that case, you become an online mall and would need a totally different type of script.
Good luck with your project.