I agree with all you said Tony. Particularly about adequate and accurate description of what you're selling.
I recently disposed of a large number of locos from the estate of a friend's father. Many were 'old school' (Mainline, old Hornby etc..) but there was a quantity of 'collectable' Wrenn, some mint boxed. I took particular trouble in the accurate desciptions and photos so that the buyer could see exactly what they were getting, even with the 'commonplace' stuff, with honest descriptions of how they performed and, where a good return was anticipated (after research) with close up shots of any faults and blemishes.
Regarding postage costs, I always charged just postal cost of the packed weight by using the Royal Mail pricelist plus £1 (cost price) when any bought-in new postal cartons for higher value items where used.
The buyers seemed very satisfied with the service (very good feedback) and more importantly I realised much higher prices that was expected.
So the moral is be informative, describe the goods as accurately as you can, provide quality snaps (close-ups where appropriate) and the results could well be satisfactory. Mind you there are always those out there that you'll never please and I did have a couple!
There are those that would moan about fees etc..for both Ebay and paypal but without the use of this sort of on-line auction and the convenience of not having to constantly contact the bank regarding cheque payment (I just don't trust on-line banking I'm afraid after a scare I had a while ago), Without doing it 'properly' I would never have got the level of success realised for the estate..