Shortly after Andres Alvarez, 36, got married last fall, he began to look for a home with his wife, figuring that their steady jobs, savings and good credit would make them the perfect buyers in Los Angeles. They were ready to spend $700,000. Their optimism deflated quickly.

“We thought we were the cream of the crop, but anything that was in our price range and move-in ready, there was this insane competition,” Mr. Alvarez said. They put in nearly a dozen bids, often losing to cash buyers, before finding a two-bedroom home for $650,000. “It might be a great time to buy, but it’s a horrible time to be a buyer,” he said.

Still, there are plenty of skeptics wondering how long the sharp price increases can last.

“People are realizing we’ve probably hit bottom, but the kinds of spikes we’re seeing in places like California seems like history is repeating itself,” said Daren Blomquist of RealtyTrac, which monitors residential sales. “That’s not sustainable for the long term, at least not for the regular home buyer, so I think there are some warning flags there.”

Lewis Legon, a developer in Salem, Mass., jumped into the Boston market after he saw how many people were showing up at open houses. “It was like Times Square,” he said of one open house, at a property listed for $1.5 million. He beat out two dozen other bidders by offering $1.8 million in cash, not the first time he had made an all-cash offer.

“The first time I was ready to have a heart attack,” he said of all-cash buy. “But it makes you a more attractive buyer and helps you stand out.”

He also waived the inspection clause, an increasingly common practice. While offers have typically included appraisal clauses, allowing buyers to back out if the home was valued below what they were willing to pay, offers today are more likely to include escalation clauses, saying buyers will pay an additional amount over the highest bid.

“Buyers are taking a lot more risks than they ever would before,” said Dana DeSimone, a Boston real estate agent who called the current market an “insane asylum.” “I don’t know that I’ve ever heard of waiving the inspection contingency on a 150-year-old brownstone until now.