Flipping houses is edging out renting as real estate investors' favored income strategy. But hold-to-rent is more popular among people getting only one property.

Auction.com, an online real estate marketplace, analyzed the intent of investors bidding on homes at auction in the fourth quarter of 2014. It found that half the people it polled planned to flip the homes for a profit.

How many planned to rent the homes out instead? Just over 47% — the rest were undecided.

Of course, all real estate is local. Of investors at live auctions, 72% of the bidders polled in Washington state were apt to want to flip the homes. The rate was 70.3% in California and 71% in Nevada.

Of investors at online auctions, 58% of bidders in the South planned to rent out.

All other regions topped 50% too, except the Northeast, where only about 47% planned to rent out.

"It's probably not a coincidence that some of the highest-priced markets, such as California and the Northeast, are seeing more flipping activity, since higher-priced homes are more difficult to rent out profitably," said Rick Sharga, Auction.com's executive vice president, in the study release.

"But it's also very possible that part of the reason we're seeing an increase in flipping is that in many of these markets, there's simply not enough new or existing home inventory to meet buyer demand," Sharga added. "That spells opportunity for real estate investors who can buy, fix and flip a property quickly and efficiently.

Of people who called themselves real estate investors, just over 51% planned to flip.

Of those who said that they were working on behalf of another investor, more than 59% planned to flip.

Of those who described themselves as one-time buyers, though, only about 28% were aiming to flip the homes, and about 69% planned to rent them out.

Bidders who showed up at a live real estate auction were more likely to plan to flip properties — 56%. Of the bidders at online auctions, though, 55% were planning to rent out, according to the Auction.com real estate investor activity report.

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