Thoughts on this -
Investor is contemplating selling rental real estate. He believes our area is nearing a peak market. To evaluate he thinks - if I sell for $X, my cash flow is $Y. If I continue to rent, it would take me 12 years to make $Y cash flow. His base line is 10 years. Less than that, might as well keep renting. More than that too long to wait for the money, should sell.
I am having trouble articulating why I don't think this is a good evaluation method. It doesn't take into account continued appreciation if you don't sell the property (or continued rent increases). Or the potential earnings on the cash flow if it is re-invested.