The only way that could work would be if they bought from you, paid with Paypal and you posted only to the address on the Paypal transaction page. That would mnean they would have to change the delivery address every time they purchased from you.

How are they going to make any money doing that especially as most of your items are under twenty five bucks? They would have to advertise the items at a much higher price than you are charging, if they can be sold for more why give somebody else

the extra profit?