People often try to figure out when is the best time to buy investment property, like someone has a crystal ball or something. I think it would depend on if you are interested speculating for a short time or interested in a long term real estate investment. In my opinion if you want to speculate there is always Vegas, if you are interested in a long term real estate investment, since historically real estate has gone up in value over time, that would make it always a good time to invest in real estate, just meaning some times the return on your money would take longer than others.
For those who want their ROI a little sooner than latter I read a report compiled by U-Haul today, According to U-Haul the report calculated the growth cities based on the percentage of inbound moves vs. outbound moves. The report was compiled based on nationwide trends in cities if all sizes and no surprise to anyone living in the Phoenix area, both Phoenix and Mesa made the list of positive migration.
So maybe you want to speculate in investment property, buying real estate now that inventory levels are extremely low, more people are moving into than out of the Phoenix area and homes are selling for less per square foot now than they have for years.
Or you are interested in a buy and hold strategy interested in positive cash flow every month, favorable tax benefits and appreciation over time, making now as good a time as any to buy investment property.