My understanding gained from a large group of buyers of varying tastes and skill levels is that they like full disclosures of any work done to the best of the sellers ability to detect same, the sellers interpretation of the grade and overall impressions of the note and a suggestion to grade according to your own standards. Cheap notes of under $100 or at that level people generally dont expect as much effort invested into the description as they do on a $1000 or $5000 note. I can tell you that the online disclosures are generally far better than those in B&M dealer price lists which generally only have a price and grade.
Marrying the approach above to an all expenses paid refund policy creates a sense of increased comfort.
Also shipping on an approval basis, before payment has been received, also is a good approach used for existing clients in many cases.
The most important thing is to listen to your clients and improve and adapt as they request.
You may see a higher instance of inaccuracy or false information on eBay because the barriers to entry are less than they are in the B&M world. Anyone can set up shop with a computer and a banknote. Furthermore you have "one off" sellers simply looking to dump what they just found and are trying to sound like they know what they are talking about.
The problem raised here exists in all markets to one degree or another and I have a list of B&M dealers who sell a whole lot slicker than the description from the seller referenced here. In fact I have had a very major dealer attempt to sell a forged signature on a heaviliy restored, very high end note 1) not telling me the signatures were forged and 2) the piece was heavily restored. Naturally both details were discovered with the help of a highly trusted advisor and not purchased.
Then there are the B&M's who rely on the little old ladies (widows) finding their yellow page ads to bring in their paper money finds and inheritance so they can "accidentially mistake" a Queen Mary 1924 $5 for a 1935 $2 and not lose any sleep over it when they pay 50% of book based on a 1935 $2 price.
The buy side industry ethics are even more, how shall I put this, "interesting" than the sell side ethics, this point cannot be stressed enough.
I would strongly suggest that picking on eBay sellers probably will not serve the B&M industry's best interests and attending to the more important outstanding matters in the other thread would be more useful.
Respect on this matter is a perfect mirror, you get what you give.
Troy