[hlzfqcbu] Should you buy?

Should you buy a good at a given price?

Economists wrangle with price formation, but let's also consider this normative version of the question from the perspective of the consumer.

It's an important question, because with all kinds of psychological tricks marketers try to convince you to buy ("a fool and his money are soon parted"), and in the face of them, great suspiciousness by some consumers not to buy, it's hard to know whether you are even remotely making the right decision.

Even if you had access to the ultimate tool, views into alternate future universes comparing what your life would be like if you did or did not buy, it's still a tough question: some things might turn out better in one, some better in the other universe.

Sometimes, after the purchase decision, you can look back and conclude, that was a bad decision.  But how can you be so sure?  What would your life have been like if you had made the opposite decision?

Setting aside the general problem as hard, what are the easy cases?  Certainly identical goods at different prices, but are there others?

Two ideas:

Create a tool to help consumers, which shields them from some marketers' psychological tricks.  At least for the easy cases, if they exist.

A consumer study, which prescribes two groups different purchasing strategies, and compares measures of quality of life afterward.  Averages and different consumers are substitute for the fanciful alternate universes tool above.