I know this is an old post but eBay is something that I know a little about. I started on there a little under a year ago and became a powerseller within 3 months, then set up another I.D to sell different items which acheived gold level powerseller status in a month.
Its true that some items can take a while to source but if you know where to look I can usualy find an item i'm looking for within a couple of hours, and if you use a little caution you'll avoid the con artists.
My dispatch process is really simple with each purchase having a bar code and I simply print a lable and scan it, meaning I can pack 100 items and email the buyers to say their item has shipped in half an hour. I still use my local post office but have been shown how to use the Royal Mail system so again that takes no time at all and they are very polite as I spend a fair bit in there.
If you are selling something that you don't own you must state it in the listing, its far easier and less stressful to operate a JIT delivery system that keeps your overheads low.
eBay offers something that no other place does, a cheap medium that reaches 10's of millions of people all over the globe. Sellers may come meaning that the price for your item goes down for a bit, but as long as you offer good customer service and don't try and charge too much the other seller will be forced out and you can raise the price.
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