Watching existing home “for sale” inventory is very helpful. As an example, the increase in inventory in late 2005 helped me call the top for housing.
And the decrease in inventory eventually helped me correctly call the bottom for house prices in early 2012, see: The Housing Bottom is Here.
And in 2015, it appeared the inventory build in several markets was ending, and that boosted price increases.
I don’t have a crystal ball, but watching inventory helps understand the housing market.
This graph below shows existing home months-of-supply (inverted, from the NAR) vs. the seasonally adjusted month-to-month price change in the Case-Shiller National Index (both since January 1999 through March 2021).
In the May existing home sales report released last week, the NAR reported months-of-supply increased to 2.5 month in May. There is a seasonal pattern to inventory, but this is still very low – and prices are increasing sharply.