I sold many photo items on ebay over almost 20 years, including Leicas and Hasselblads and their lenses, but have stopped after experiencing ebay's mandatory return policy. If a buyer checks the ebay box "Does Not Meet Description" then you have 48 hours to authorize a return shipping label, and after the item comes back to you you have 72 hours to issue a refund of the purchase price plus shipping, or in each case ebay will do it for you and charge you. It matters not that the item functions properly and matches the description precisely - if the buyer says it doesn't then the sale WILL be fully unwound. At least ebay is "nice" enough to give you your selling fees back.
I don't know how long a buy has to demand a return that ebay will enforce. On the one that came back to me, the process was started about 3 days after the buyer got the lens (I think he used it over a weekend and decided to get his money back.) I had another buyer write me 46 days after he got the lens (and after he had left positive feedback) claiming the aperture blades were stuck and wanting his money back. When I said no he immediately wrote back and said he had had it repaired and would I contribute $120 toward the repairs. I haven't heard from ebay on that one, but I've decided not to wade into that pool again. I do look at the site to get an idea of what things are selling for, though.
Ken, I have purchased a flash unit, and most recently an iPad Mini from fellow UHH members, and the outcome has been very satisfying. I agree with Dave, why not off your equipment for sale here on this site?
Just bought another item from a UHH member and am very satisfied. I'd start here.
If I’m selling a camera and some lens for that camera to a camera store through the mail which will give me the most profit? Sell them by the piece or all together?
Definitely piece by piece. I recently asked several of the buyers at (the biggies) some pertinent questions about selling to them. One piece at a time, keep all the fancy accessories and extra batteries for a separate sale. They don't give anything extra for 3 extra batteries, or filters, or xxxxxx. Camera (body) charger and battery. Lenses are priced better separately. Ebay is different, packages can sometimes make a difference, but not always.