Usually it's either the barbers that are acting as the "canary in the coal mine" (or parrot in some cases) or the the taxi drivers. For example, back in 2000, my barber was advising me on what to buy in the stock market, she acted as a specialist. Nowdays , she advises on housing...
Today, this role is clearly being taken over by the taxi drivers.
In 2001, prices sharply went up and we add a recession.
In 2008, prices sharply went up and what are we going to have?