Some 65% of respondents said they were overstretched financially and the costs of Christmas had forced them to take action.
Matt Hutchinson, director of Spareroom.co.uk, said: "It seems that Christmas has acted as a tipping point for many home owners whose finances have been stretched to the limit by the impact of the recession.
"With Christmas over and done with, homeowners are using the start of a new year as the motivation to get their finances in order. As a result, we have seen unprecedented levels of live-in landlords advertising in the first two weeks of 2010."
The average weekly rent stands at £87, Spareroom said.
Click here to read full report in the Daily Telegraph.
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