Thrift shoppers love going to thrift shops because the inventory is ALWAYS changing.
I've seen many many shops that don't rotate their stock. What I mean is that if an item doesn't sell in 2 weeks to a month get rid of it. You need to make room for items that will sell.
I know plenty of shops that are overwhelmed with donations because they're not rotating the stock.
Use a colored tag system, either stickers or price tags, and rotate them.
4 different colors are best.
Week 1 red
Week 2 blue
Week 3 yellow
Week 4 green
Week 5 purple
during week 3, red tags are 25% off
during week 4 red tags are 50% off and blue tags would be 25% off
Week 5 you have pulled all the red tagged items and then start all over.
Rotation of your stock is critical to your store's success.
I'm going to use this system at a local shop I volunteer at.
I'll let you know how things go..
Different colored tags and stickers can be purchased here...
http://www.hangersunlimited.com