Sometimes, presumably when vendors are honest & the parts have been on the shelf for a while, they will honor their original purchase cost & margin. Other times they ratchet the prices up on existing (old) inventory if market prices have increased & pocket the difference. Usually stagnant inventory is dead money so typically reduce prices with a sale & get it out the door. One thing I've noticed is my KBC & Travers paper catalog prices look nothing like current prices. Some have increased significantly, some just a bit. Not too many things seem cheaper but its more of a gut feel than actual comparison. I'm not sur why but KBC sale flyer seems to be +/- the same stuff, issue after issue, year after year. I guess use that to your advantage, but a bit of variety would be more useful.