canny
adj.adj. very smart and good at making clever choices. You use this to describe someone who is careful and knows how to get the best deal.
adj. possessing or displaying shrewdness, prudence, and a keen sense of opportunity. Often used to describe a person's ability to make wise financial or strategic decisions.
He is a canny businessman who always gets the best prices.
The old man was a canny trader who managed to save enough money to retire early.
In a highly competitive market, a canny investor must remain vigilant for subtle shifts in consumer behavior that others might overlook.
Northern English dialect, from can (“to know”) ( + -y), from Middle English can, first and third person singular of cunnen, connen (“to be able, know how to”), from Old English cunnan (“to know how to, be able to”). Compare Scots canny, English cunny, Old English cann (“knowledge, assertion”). More at can, cunning.
Back-formation from uncanny.
can (“more or less cylindrical metal container”) + -y