I think the Speed champions, Potter BH, Sleeping Beauty Castle, and Juniors Incredibles sets are no brainers at 75%. The other sets I wouldn't look twice at if the discount was 50% or lower, but at 75% it would be hard to pass on those as well. The problem here is the timeframe you set for yourself to move them. Most of those are still available in stores, and on sale, so you'd have to offer a substantial discount to the buyer. Otherwise what's the benefit to them to buying from you vs just buying from a store? There might not be much profit left for you in that scenario if you need to sell quickly. Ideally you should buy these and store them for 2-3 years. Once they retire and are unavailable at retail your buy in will give you an advantage over other sellers. At that point you could sell at msrp if you wanted to and still make a decent profit.