Why is it different if you can afford the item at 70% off? If you can't afford it, don't buy it. If you can afford it and you want it, get it. If you want an $800 pair of pants but can't afford to spend $800, don't buy them. If they drop to $200 and now you can afford them, then buy them. Not that difficult. Now if you're buying those pants at $200 just because they're on sale, even though you don't particularly need or even want them, then that's another story. People make a lot of fuss about nothing in this thread when I think everyone, or at least a lot of people, probably agrees on the basic idea I just laid out. And of course you can apply that principle to a single unit. The principle is the same no matter how many units you're talking about.