Real estate agents across the country are seeing home prices edging upward, a trend that may be send more potential clients in search of options to afford a monthly mortgage payment.

CNBC reported that number of adjustable-rate mortgage originations jumped just over 40 percent from the first quarter of this year to the second. These options offer lower interest rates than fixed-rate loans, and today’s ARMs usually have a fixed period of at least five years. That means the rate can change after five years. Still ARMs are considered riskier than the classic 30-year fixed mortgage.

While mortgage rates remain very low, historically speaking, they have been inching up. The vast majority of homebuyers favored the safety of the 30-year-fixed rate mortgage since the housing crash, but weakening affordability is now changing that.

Frank Nothaft, chief economist at CoreLogic, pointed out that home prices have been rising steadily for the past three years. They had been holding steady, but seem to be heating up again.

“One thing that’s helped to fuel demand, and certainly home price growth, as much as the lean inventory of for-sale homes is that mortgage rates have really cooperated.”

One problem, according to Matthew Pointon, property economist at Capital Economics, is that close to half of the nation’s top 50 housing markets are overvalued, in relation to income and employment growth.

“Prices are being driven up by very tight market conditions. On a per capita basis, the number of existing homes for sale is at a record low, and buyers are therefore having to up their offers to secure a home.”

Tight lending standards are putting a lid on growth. Pointon maintains that home prices should actually be rising by more than 10 percent, given the tight supply.

“Cautious appraisals are preventing desperate buyers from bidding too much for a home, as are strict debt-to-income ratios.”