On your website, do not offer your cheapest service or lowest priced item only. Always offer high-priced alternatives so that your client will have an emotional point of reference. This is called the Principle of Contrast.
For example, if a cruise line website only shows the lowest price for a ship cabin, there is no real incentive to buy a higher priced cabin. If they also show the exorbitant price of the spacious, luxurious "suite" on the top deck, then anything in-between looks like a bargain.
Here is a fascinating article on this subject: The Principle of Contrast
