If you are looking to sell Airsoft guns and supplies online or on eBay then make sure you do your homework. There are many companies selling Airsoft products on the internet.
What you should do is find a niche within the Airsoft market. There are tools to do this but if you want to do some free basic research then follow these instructions. Brainstorm various types of Airsoft related products and services, and write these down. Then go to eBay and search the listings for these items. If there are relatively few items for sale then you might have yourself a good niche.
Once you find a niche in the Airsoft world then find a good Airsoft dropshipper or Airsoft wholesaler. There are many wholesalers and dropshippers on the internet, but it is difficult to find the ones you can trust. Look for a eBay seller community that you can join to ask others which dropshipping companies are best. These communities have other benefits besides which dropshipping companies are best. You can also get valuable selling advice from more experienced eBay on online sellers.