It may depend on how specialized the product is. I bought a
holding tank on ebay from an inventory sell down. It was one third the cost of
purchasing it from the manufacturer or another dealer. Some
books you might
purchase from Amazon will be shipped from another supplier you could just as easily buy direct from, possibly
Bluewater Books or Landfall
Navigation. Defender has a good selection of sailing supplies. West
Marine also can provide a decent source of product IF it is on
sale. Some products can be found at Cabelas or another online sporting goods retailer.