Broker Dave Ferguson stands in front of a house in Caldwell. The five-bedroom home is in a quiet spot, shrouded in trees. In this case, that’s not a selling point. Ferguson points upward.

“It’s a cedar-shake-shingle roof,” he says. “And it’s so bad with the trees that they deposit their limbs and leaves, and it actually turns to soil because it doesn’t get brushed off.”

The soil has led to something else: weeds growing out of the roof. There’s also the fact that the house was built in 1972, and no remodeler has touched it since.

Still, an out-of-state investment group has made an offer.

“This investor that I’m working with is specifically interested in homes that are undervalued and that might be in disrepair, like this one,” Ferguson explains.

The demand for this home is one sign that there’s something unusual happening in the Treasure Valley. While national figures show that the housing recovery is slow, at best, Boise is one of a few U.S. cities that have seen a fast run-up in demand and prices.

Investors and homebuyers are in stiff competition, and both say there aren’t enough homes to go around. For example, Ferguson’s investor client would rather buy newer houses, and make simpler fixes. But deals like that are in short supply.

Just ask buyer Samantha Boucher.

“Yeah,” she says. “We were all sorts of frustrated.”

She and her husband, Chad Boucher, know as well as anyone how tight the local housing market has become. A year ago, Idaho had one of the highest foreclosure rates in the nation. Prices hadn’t touched bottom. By early this year, it was a different story. Chad Boucher says the quick shift was hard to take.

“Everything we put bids in on, it eventually went way above our price range that we were thinking for that house,” he says. “We were just like, “Man, we’re going to be outbid by everybody, so why would we keep doing all this legwork for no actual gain, because we can’t go higher than these other people?”

The Bouchers have an advantage many buyers don’t. Samantha Boucher is in the know. She’s a real estate marketing assistant. On the other hand, the two of them are first-time buyers looking for a house in the most competitive price range: under $150,000.

In one case, Samantha Boucher says, their competition was an investor who paid cash. That made her a little indignant. “I really wish there were things in place more often that allowed people that are first-time homebuyers, going for the American Dream and all of that sort of stuff, to actually have a chance before the investors got to have the pick, you know?” she says.

The Bouchers were about to give up and keep renting, but fortune smiled. They got to pick up the keys to their new home last month.

Realtors are divided about who is driving the Treasure Valley’s housing market. Some say investors account for 20 percent of their sales. Others say more than half.

Either way, it’s clear the extra demand is affecting prices. The market’s turnaround has left people scratching their heads, including Marc Lebowitz. “Not only is it such a great distance from where we were last summer,” he says, “but it also seems to have come on more quickly than anyone expected. We’re going to look back and go – ‘Gosh, that was fast!’”

Lebowitz heads the Ada County Association of Realtors. He says one measure of a real estate market is the number of homes available, and how well that number matches demand. A six-month supply indicates a healthy and balanced market. But the number of homes now for sale would only satisfy three months’ worth of demand.

That shortage has kicked the market into high gear. Lebowitz will admit that gives him pause. “I’m solidly convinced that we’re in a strong recovery,” he says. But he’s not sure the pace is sustainable.

Lebowitz tells a story about a modest home that recently sold for 20 percent above list price. Immediately, the prices for nearby homes jumped. That’s notable, because escalating prices can make for risky decisions. Risky decisions can make for bad investments. And the recession was a lesson in where bad investments can lead.

Still, Lebowitz has sunnier expectations for the Valley’s market. To understand why, look no further than Samantha and Chad Boucher. They’re happy with the home they bought. It was at the peak of their price range, but they think it’s a good buy. After all, prices are still far below where they were five years ago. Now, the Bouchers plan to watch their investment grow.

As for Dave Ferguson? His out-of-state investor got cold feet and decided against the Caldwell home. Within 12 hours, Ferguson had two more offers. Both were from investors.

Molly Messick: mmessick@stateimpact.org, Twitter: @mollymessick