Answer:
anchoring bias
Step-by-step explanation:
In business, anchoring bias happens when a consumer relies on pre-existing information (in this case sales price) to make their purchasing decisions. E.g. a sales promotion where a before price is set as the anchor to show that the after price (with the discount) is a really good deal.
In this case, John started to negotiate a sales price using the sticker price as an anchor, and ended up making a good deal because he got a $2,000 discount.