The Treasury fears embarrassment and pointed fingers; selling at a loss would echo the decision a decade ago by Gordon Brown, then the chancellor, to sell much of Britain's gold at the bottom of the market. Too bad.
A small quantity only could be sold; and the coal masters and the coal proprietors find it more for their interest to sell a great quantity at a price somewhat above the lowest, than a small quantity at the highest.
To win in this game, you need to know the maximum that a shoe is worth as a buyer, and then the minimum you could flip it for on today's market based on current conditions.
So the expression and up is used when you're giving the lowest price of something, but also telling the person that there are more expensive items or things that you are selling.