By Ernest Scheyder and Ilaina Jonas WILLISTON, N.D./NEW YORK (Reuters) - Money and workers are pouring into Williston, the capital of North Dakota's oil boom, but the only department store in town is a JCPenney, with a facade straight out of the 1950s. "We desperately need some kind of shopping center or mall here in Williston," said Rev. Jay Reinke, a 20-year resident and pastor of Concordia Lutheran Church. You have to drive hours to find decent shopping. That drive is not getting shorter anytime soon. Real estate developers are finding loans and investments hard to come by from Wells Fargo, private equity firm Carlyle Group and other major American financial powerhouses for new department stores and other commercial property, as well as residential developments. While billions of dollars in oil money may be rushing into North Dakota, big money has resisted financing large real estate deals there, barring some projects entirely and leading other developers to self-finance. Many would-be financiers say the North Dakota oil patch real estate market is too hot to handle right now, with demand for housing outstripping supply, fueling high prices. The average two-bedroom apartment in the oil patch rents for more than $2,500 per month, helping drive land prices sky-high and sparking concern about a bubble. National homebuilders such as Pulte Group, D.R. Horton and Hovnanian Enterprises have yet to enter North Dakota. Pulte said it was focused on improving its market share on the East and West Coasts, as well as some Midwest states. The other two declined to comment. Part of the hesitancy stems from the reluctance of energy-field workers to move their families full-time to North Dakota, a step that would cause them to spend more money locally. The state's biting winter weather and remoteness have discouraged all but a few families, realtors say. Data about home-building permits suggests workers are still keen to rent apartments rather than invest in housing and settle down. Only 20 permits were granted in Williston during the first five months of this year, compared to permits to build 482 apartment units, according to the city's building department. As recently as 2010 the number of homebuilding permits in Williston, a city of about 16,000, far outpaced apartment permits. "At first we thought we really had to run fast to get position in the homebuilding market, and now we see a landscape that frankly isn't running away from us," said Terry Olin, a North Dakota native now exploring real estate projects in the state with Switzerland-based investment company Stropiq LLP. Many banks remain wary of the past repeating itself. North Dakota saw a surge of oil activity in the 1950s and 1980s, only to have the flare-ups burn out, leaving many residents, municipalities and banks in debt after funding large projects. Williston alone had millions in debt from the 1980s oil boom as recently as 2005. "What we don't want to do is go into a community like Williston and engage in speculative lending and not have an exit strategy," said Dan Murphy, Wells Fargo's regional president for North Dakota, South Dakota and western Minnesota. We're happy to make loans. We want to be repaid. The hesitancy comes even as Marathon Oil, Exxon Mobil, Statoil and dozens of other energy companies spend billions of dollars to extract North Dakota's oil and natural gas. Many bullish geologists say the North Dakota oil boom will last for half a century at least, citing technological advances that have made supply easier to reach. The Peace Garden State has the lowest unemployment rate in the nation and the fourth-lowest foreclosure rate on home mortgages. But many of the new jobs are filled by men living in temporary work camps who send chunks of their paychecks back to their families in other states, rather than put money toward longer-term investments locally. That makes it tough for developers to argue oilfield salaries - many of which exceed $100,000 per year, far higher than the national average of $40,600 - will be spent on permanent housing or at stores that could anchor shopping centers. "I don't think anybody can clearly articulate how any of this is going to develop," said Robert Stuckey, head of private equity firm Carlyle Group's U.S. real estate business, which has held off investing in North Dakota's oil patch. There is inherently some ambiguity and therefore some risk to it. Some developers have decided to write their own checks in the meantime. Private equity firm KKR, which broke ground last month on 330 apartments as part of a 164-acre housing development, has yet to convince a bank to fund a construction loan. Plans for the total project include 810 apartments and lots for more than 300 single-family homes. "We believe there are financing alternatives available, but we're prepared to build all cash," said Michael Friedland, a principal with KKR. KKR and smaller developers acknowledge that spending their own cash now, with the hope a loan will come later, could be considered a risk too large to take. But they feel science is on their side. The rise of horizontal drilling, a complex process where energy companies drill down two miles then turn right to drill an additional two miles to extract oil, has vastly increased the number of wells tapped in North Dakota. The U.S. Geological Survey in April doubled its estimates for the amount of crude oil recoverable from the state's energy-fertile plains to 7.4 billion barrels. Despite that bullishness, Bank of America, JPMorgan Chase and Citigroup, the largest American banks, don't have retail branches in North Dakota, which has the distinction of being the least-visited U.S. state. While a few national retail and restaurant chains, including McDonald's and Wal-Mart, have opened in Williston, they've found they need to pay workers starting hourly wages around $15 to $16, far higher than their other locations nationwide. Home Depot Inc plans to open a small satellite store this summer inside an old warehouse in Williston. The location, the company's first in the city, will employ about 25 workers and have only a fraction of the products offered in its big-box stores. So far, Home Depot said it's holding off on a decision to build a new hardware store in the heart of the oil patch. Reporting by Ernest Scheyder in Williston, North Dakota, and Ilaina Jonas in New York; Additional reporting by Anna Driver in New York; editing by Edward Tobin and Prudence Crowther