In the housing market today, it feels like what goes up doesn’t have to come down.

It looked like home prices were finally cooling off late last year after price spikes that began during the pandemic. Nationwide, prices dipped gradually in the second half of 2022 as mortgage rates climbed in response to rising interest rates. And some areas where a lot of new homes had been built — like Austin, Texas; Boise, Idaho; and Charlotte, North Carolina — saw significant price declines.

Granted, that was a double-edged sword for many people. Higher interest rates tend to bring home prices down, but that’s because they make it more expensive for buyers to borrow money to finance their purchases.

The rate hikes were not enough to undo the big price gains of the past few years, especially in parts of the U.S. where home sale prices already run well above the national average, but the change came as a relief for many people.

Then something even more surprising happened early this year. Prices started going up again. Potential homebuyers who may have breathed a sigh of relief a few months ago are now staring at an improbable double whammy: Prices are at all-time highs even with mortgage rates at 23-year highs.

The average U.S. rate for a 30-year mortgage was 7.49% on October 5, according to government-backed lender Fannie Mae.

In fact, an NBC News analysis of data from Zillow found that estimated mortgage payments have increased in more than 500 cities since the end of 2020, with payments doubling in more than half of cities.