A customer pumps gasoline into his car at an Arco gas station in Mill Valley, Calif. Getty Images

Today's homebuyers don't need another headwind. They're already facing one of the tightest, most competitive housing markets in history, with home prices rising far faster than incomes, mortgage rates climbing and the supply of homes for sale continuing to shrink. Now add higher gas prices to the toxic mix. The average price for a gallon of regular gas is up 60 cents compared with a year ago, according to AAA. While there is no specific data on how they correlate specifically to home sales or prices, gas prices definitely play into consumer confidence about personal finances — both going up and coming down. When prices fell heading into 2015, some claimed that was a boost to the housing market.

At the time, analysts at Deutsche Bank estimated that the 23 percent decline in gas prices added about $100 in monthly income for the average American. That, in turn, translated to an 11 percent boost in purchasing power on a starter home. On the flip side, higher gas prices take away from both real and emotional purchasing power. Paying more at the pump makes people feel like they have less money in their pockets overall, and homebuying is an incredibly emotional enterprise to begin with. Mortgage rates are also at the highest level in seven years and are clearly on an upward trajectory. That makes it more difficult for first-time buyers on the margins to both afford and qualify for a home. "Anecdotally, I can tell you that it does become a reason not to buy a new home in what we affectionately call the 'drive till you qualify' areas," said John Burns, CEO of John Burns Real Estate Consulting.

Where rising prices will hit hardest