As far as the sales value of your Trailwise bag, Bill, I regret to say its probably pretty low. Sleeping bags arent like bicycles or stereo receivers; there arent many classic" models out there. Maybe you could put it on Craigslist.org and get $50 for it, but that would be doing very well. You also could try GearTrade.com, a fairly new site thats sort of a Craigslist for the outdoor set. You can post outdoor-related items on GearTrade and sell them, and, of course, you can buy stuff as well. Setting the price can be a challenge, but try to find similar items that have sold recently on eBay. Its my experience that anything that sells on eBay goes for pretty much exactly what the market deems it is worth.
Still, rather than try to collect a few bucks on a bag that has been amortized a hundred times over, Id suggest that use your sleeping bag to spread some joy, in the same way it has kept you warm all these years. You could, for example, register on your local Freecycle.org site. Thats a wonderful site where people post items that they no longer want or need, giving them away or getting them. Youd probably find a very grateful person who would take your bag and give it a happy life for another 10 or even 20 years.
Better yet, try to find a young person who would love to try some camping but is having a hard time getting equipment assembled. Try local Boy Scout or Girl Scout groups, any sort of YMCA establishment, that sort of thing. Then take the IRS deduction and call it all good!
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