If the machines are complete but not working, have decent playfields and backglasses, then I'd say $100-$150 each. A working one is $500-$600. But, the market is soft, as Vic stated, so it may take a while to find a buyer.
Condition is everything in terms of the price.
I'd pay $100 for just a Variety backglass that was in 9 out of 10 or better condition -- but that's because I already own a Variety and would like to upgrade the glass that I have. Do you ever travel to Cincinnati?