A new development is catching home buyers off guard as the spring sales season gets under way: Bidding wars are back.

From California to Florida, many buyers are increasingly competing for the same house. Unlike the bidding wars that typified the go-go years and largely reflected surging sales, today's are a result of supply shortages

"It's a little surprising because we thought bidding wars were done with," said Andy Aley, who is looking to buy his first home in Seattle's Beacon Hill neighborhood. The 31-year-old attorney was outbid this year when he offered up to $23,000 above the $357,000 listing price and agreed to waive inspections and other closing conditions.