Wealthy part-time residents, deep-pocketed golfers and affluent families have quietly transformed north Scottsdale into a luxury-home hub in less than a decade.

Home prices in the 85260 ZIP code, still a relatively affordable part of the sprawling north Scottsdale market, shot up almost 18 percent in 2003 after single-digit gains in the previous four years, according to The Arizona Republic's Valley Home Values report.

The typical house in the area that is split by the Loop 101 and home to the booming Scottsdale Airport commercial hub now costs about $324,000, more than double the median home price for the Valley.

In the city overall, prices increased 10 percent between 2002 and 2003, triple the increase in Mesa.

The increase is even more dramatic considering that a new Scottsdale home sold for $162,000 in 1993, according to the Arizona Real Estate Center. That's a 237 percent jump. Part of that is because a wider variety of houses was being built in the former bedroom community.

Now most of the city's new homes are going up in north Scottsdale, which starts at Bell Road and spans north and east to the McDowell Mountains.

Carol Greenidge moved from Colorado to Arizona in November and closed on a 2,100-square-foot house in DC Ranch in January.

She likes being close to her daughter, who lives in Cave Creek, as well as the freeway and the convenience of nearby shopping, art galleries and restaurants. In Colorado, she drove 20 minutes to Safeway. Here, it's a minute away.

Greenidge, 58, also looked for houses in Grayhawk, Troon and McDowell Mountain Ranch before she bought in DC Ranch.

A psychotherapist in Colorado, she wanted a change of scenery and is looking for a new occupation, maybe something involving art, that doesn't involve clients calling at night.

"The 7-foot blizzard last March 19 had something to do with it," she added. "I was housebound for six days."

Greenidge bought in a Scottsdale area where overall values have been on a roll. The average house overall, new and resale, in the 85255 ZIP that is home to DC Ranch cost $249,100 in 1998. That number jumped to $426,000 last year. The gains came amid a falloff in the number of sales.

There is less land to develop there and in the adjacent ZIP codes, which make up the pricey north Scottsdale market.

And prices are expected to keep climbing as land becomes scarcer. DC Ranch had 1,000 people interested in new neighborhoods before they were publicly announced in February.

Don't expect another wave of large luxury enclaves such as Troon, DC Ranch, Grayhawk or Desert Mountain.

"Supply and demand is driver of the marketplace in Scottsdale," said Ron Coleman of Arizona Land Advisors. "It will continue to be that way for the next 10 years. That equation will continue to drive prices higher."

Coleman noted that Scottsdale is nearly built out and much of the state land in the area is targeted for preservation, pushing prices for remaining land higher.

That means developers who shell out big bucks for land need to build the sort of projects that deliver high returns rather than production subdivisions.

"Scottsdale still has room to grow," he said.

"But we will be more like Tempe and Buckeye. We will continue to grow, but it will be all about quality rather than quantity."

Scottsdale covers 117,000 acres. Developers and investors already tied up most of the vacant land available.

That's one reason why about 1,000 potential buyers are asking for information about some new neighborhoods in DC Ranch months before models open later this year. Brent Herrington, vice president of DMB, said the development company may use a lottery to pick buyers if there's a huge demand.

"We're hoping we don't have to implement that kind of tool," he said. "But it just becomes too much a circus."

Considering the high prices and the Valley's relatively low median income, many wonder who can afford to buy there unless they are selling a high-priced house out of state.

But Norm Kitzmiller, a north Scottsdale real estate consultant, said many of the area's residents work in the Valley and have been here for a while, which is the opposite of how it was in the early 1990s. Many of them, he said, are local executives, doctors, lawyers and entrepreneurs.

"There's a lot of quiet wealth in the Valley," he said. "It's not just money from out-of-town buying luxury homes in north Scottsdale."