For years, the costs of renting and owning were relatively in sync. That changed in 2021 when the cost of home buying started to skyrocket. And unlike many pandemic-era trends that have since reverted to the norm, this particular one is here to stay "for some time," according to CBRE.

"With average mortgage payments 38% higher than average apartment rents as of year-end 2023, many U.S. households are continuing to rent rather than buy a home," they wrote. "Even though the premium to buy a home may come down over the next several years based on home-price, interest-rate and rent-growth forecasts, it is expected to remain high enough to keep today's renters renting for longer."

To be sure, there were periods since 2001, like in 2005 through 2007, when ownership was on average as much as $500 a month more than rental, not counting insurance and assuming a 10% downpayment. Even then, within four or five years, the costs flipped, which would have allowed refinancing to reduce the homeowner's cost and kept costs below rising rents.