Buy By Prompt
BTC

The purchase decision matrix

Map every purchase onto cost vs research-needed. Stop over-researching $20 cables and under-researching $4,000 laptops.

Most people invert effort: three hours on a phone case, twenty minutes on a sofa. The matrix is how you pick how much AI (and human) work a buy deserves.

Low research neededHigh research needed
Low cost (<$50)Validate in one pass — then buyQuick rank of 3 options
$50–$500Feature / compatibility checkFull matrix, return window
$500–$5kUnusual — ask why research is lowMultiple sources, used vs new
$5k+Red flagMulti-session workflow, human confirm

How to use it with a model

Do not paste “what laptop should I buy?” Put the cell in the spec: “This is a $1,200 high-research buy. Produce a five-row matrix. Do not recommend a $4,000 machine.”

Tie this to buy / wait / skip. High-research cells almost never skip the wait option (new chip next month, sale cycle, measure twice).

AI-specific traps

  • Models average review-blog cadence and sound certain
  • Prices in training data are stale — you click the live page
  • “Best overall” is not a cell on this matrix