I think the financial loss (or perceived loss) is what holds me back from sales at times. I think perhaps I want more than the market wants to pay (mind you, the market generally doesnt want to pay anything approaching reasonable when the market is gumtree)... and I haven't yet braved ebay because I am reluctant to post to people I know nothing about. I probably need to examine that more closely.I hear you Sue and also Ray. I've just sold off a perfectly good kit (GH2 and 5 lenses) to invest heavily in an X-E1 and 5 lenses. Did I need it - probably not. But I'm enjoying shooting every day in August and I'm trying to take photographs rather than snapshots.
I've met 2 of the lens buyers in person and conversed at length with one on eBay and I know I've passed on the excitement I had when the gear was new to me. I quite often buy second hand (eg the 35 and 60mm Fujis and the body/18-55 was a demo) and consider the financial loss an acceptable 'rental' fee for the pleasure I get.
Apart from the Fuji 10-24 when it appears I'm currently free of GAS for the foreseeable future.
I get what you say about "rental" and you are absolutely right...