All depends on the quality of the Brass. You'll do good to find out how many times it's been loaded. Also, how hot were they loaded.
What brand of dies, are they rusty or well taken care of? You can get a brand new set of Hornady or RCBS dies for around $40. Rem or Win Brass (brand new) is about $45/100. Norma is more expensive.
If the brass has only been fired a couple times, and the dies are fairly clean and taken care of; You're probably getting a good/fair deal IMO.