Analysis to Set up Online Stores

My business website has been around for over 10 years - supermagnetman. I had a negative experience trying to use Ebay several years ago (the fees exceeded the cost of the item I was selling). When I tried checking out Yahoo stores they started charging me $40/month and I did not know anything about it for a year before I got it stopped. Now I am interested in finding out if there is a reasonable expectation that I could experience a noticeable increase in sales if I pursued setting up several of the various stores on the various store hosting systems. Secondly, IF it is possibly profitable to be on those stores, can any of them be set up to pull the product information and pricing from my existing website database? Thirdly, If all of these would be possible then I want to set up a project for someone else to set up the store and get everything to work. I recently awarded a contract to someone to increase the success of my Adwords campaign and it was a total waste of money. My ultimate goal is to increase exposure and sales on my website.