Cheap at half the price. Can you tell what means this?
Oh, I use it sarcastically too, but to mean that something costs more than it should -- that there isn't great value.
A: I heard you ate at the new fancy restaurant in town. How was it?
B: Well, the food was really pretty good, but it would have been cheap at half the price. (We paid a lot for our dinner.)
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.