I just talked with one of my local Gamestop managers and he told me about a promo this upcoming weekend.
Buy 2 used games get 20% off (30% with PUR)
Buy 4 used games get 30% off (40% with PUR)
Buy 6+ used games get 40% (50% with PUR)
The manager here said they were also doing the 50% (60% PUR) TIV bonus at this store as well.