This may help you:
http://jbfsale.com/files/JBFPricingGuidelines.pdf
At JBF, they say if you can't sell it at $3 minimum, then you need to make it a set (put a matching shirt and pants together) or donate it.
Everything I put in is $3-8ish??? maybe. 100% of my things I allow to go 1/2 off on the last day. I always have 300+ items in a sale and walk away with everything sold except for 10 or less things.
The sale this month will be a smaller one for me. Right now, I'm up to 179 items.