Lately I have found that some eBay trading card dealers have been spamming their past buyers and bidders when new or similar cards become available for sale. Interestingly one particular dealer seems to be selling items well above the average rate after employing this tactic.
Personally it didn’t phase me when receiving the emails. They were not regular and it was actually handy to find out that a trusted seller had listed new items. Sports cards is one industry where this kind of activity may not be negatively received on a personal basis as many buyers are repeat customers.
However I’m not sure of the implications of eBay’s Terms and Conditions on this. In addition, some countries have very strict spam laws that could, in theory, land you in hot water if you continue to send the emails without authorization.
Perhaps it could be a good idea to ask your customers after they buy from you whether they would like to join a mailing list to be alerted when you have new items for sale. This could be done externally to eBay and, as long as there are unsubcribe capabilities, you shouldn’t have any problems with spam laws.
At least one eBay dealer seems to have greatly benefited from many users all becoming interested in his high quality items at the same time.