This isn’t about the game show. it is about knowing the value of what you are buying. It is often easier to determine when something is too expensive. This happens when there is a high demand and low supply. For instance there are a lot of construction projects issued all at once and only a few contractors that can do the job. There are a lot of other factors and this is one of many.
Then how do you explain when the price is too low. Some suppliers will use loss leaders, try bait and switch or use change orders for services not covered in the contract.
You should always be considering if the price is sustainable. Which means can the supplier sell the product at that price and stay in business. Did they do a material mistake or calculation error? Do not think that companies always know what they are submitting and can live with the mistake.
Please be careful when mistakes happens. Check to see if your proposal wording allows you to fix the mistake without causing you challenges later.
As I have said before price should not be the only determining factor when making a buying decision. It does after all, have to be reasonable and most of all right.