So what does this all mean? Well, current mortgage rates are 4.65% on 30-year, fixed-rate loans. If they increase by just one full percentage point, it costs typical home buyers an additional $147 a month—or almost $53,000—over a 30-year period. (This assumes that a home is about $300,000 with a 20% down payment.)

Even much smaller increases really add up. If mortgage rates tick up by just 0.05%, it can cost typical buyers $2,600 or more over the life of their 30-year loans.

Rates are expected to rise to between 5.5% and 6% over the next two years if the economy keeps humming along, according to Len Kiefer, deputy chief economist at Freddie Mac.

Those escalations can make it harder for buyers to qualify for loans on the abodes of their dreams, forcing some to purchase smaller residences, fixer-uppers, or properties in less desirable or farther-out neighborhoods as a result. Some may even be priced out of the market altogether.

But don't panic just yet.

It's important to realize that rates are still low. Yes, they're more than 0.8% higher than they were a year ago, according to Freddie Mac data. But they're nowhere near the peak of 18.63%, in October 1981. So, you know, breathe.

"We've experienced low rates for a very long time," says Kiefer. He pointed out the last time that rates rose above 5% was way back in 2011. "[So] the increases that we've seen are likely to stick."

Mortgage broker Chris Brown has seen fewer buyers seeking loans over the past few months as a result of the increases.

"Buyers are starting to come to the realization that real estate prices have moved up significantly over the last six or seven years and, combined with higher rates, the homes they were once targeting are no longer in their price range," says Brown of CB Investments in Huntington Beach, CA. "It has forced them to either settle for a lesser home than they expected or temporarily put off the home search. [And] a lot more buyers are opting for the latter."