Most often, ebay sellers would list item for auction such as ebay memorabilia and ebay collectables. Though these items command higher profit and are unusually sought after, they run the risk of incurring higher logistical cost on shipping damages.
However, there are some VERY creative sellers on eBay. These guys are selling product that costs a few dollars to produce. Unlike the stocking problem with the ebay memorabilia and ebay collectables, they have no fear of running out of inventory. Virtually no fear of competition (no direct competition EVER).
They make as much of it as they want for a few dollars each ! And they COULD be building a great mailing list of NICHE enthusiasts.Selling on Ebay using Airbrushing skills will be a good niche.
Here's a short online video about the hidden opportunity in Ebay Airbrushing How-To