To correctly perform this glitch, I am pretty sure you have to get the people down to the Kvatch campsite place. Unless the orc lady is already there.
First off get a horse.
Any horse will do, so long as you can have an item equiped and sit on it.
For some items this doesn't work, so use only weapons, and I don't think Umbra will work.
All you do is sit on the horse with the weapon equiped, talk to her, barter, and sell her the weapon for as long as you want.
The glitch works, because you can't unequip items while on the horse, so she pays you while expecting the items, that she doesn't recieve. =)
Rejoice! Your as rich as you want!