This is a bug.
Code:
[ 6] A tattered cross-striped shirt with short fringes - a superb medium cloth armor
Price: 2 gold, 1 silver.
[ 7] A tattered cross-striped shirt with short fringes - a very good medium cloth armor
Price: 1 gold, 9 silver, 1 copper.
[ 8] A tattered cross-striped shirt with short fringes - a very good medium cloth armor
Price: 1 gold, 9 silver, 5 copper.
[ 9] A tattered cross-striped shirt with short fringes - a brand new medium cloth armor
Price: 2 gold, 2 silver, 2 copper.
[10] A tattered cross-striped shirt with short fringes - a very good medium cloth armor
Price: 1 gold, 8 silver, 9 copper.
There is a limit of five listings of a single item in the shop. Normally this wouldn't matter because all listings are grouped together, but because you have five different qualities of items in the shop, it still counts as five listings. The bugs are 1) that some of these are showing the same quality and so should be in the same listing and 2) if the item would go into an existing listing, he should still be interested in it.