Think about it... Why in the world would you buy a house for it's "regular" price after it's been put on "sale" by the builder?
If the house is 500k for example, and it was on sale two weekends ago for 430k, there is NO FREAKING WAY I'd pay the 500k. I'd either wait for it to be discounted to that level (or even further) again, or I simply wouldn't buy it.
Once you sell an asset that costly for a certain cost, that's what it's worth.