KFH is also predicting a 5 to 10% increase in selling prices over the next six months.
"During the first quarter of 2009, we have witnessed the first positive signs of a stabilising and improving London property market," Watts said.
"Although sales agreed were still 20% less than the same period in 2008, they are the best results recorded for over 12 months.
"In London, selling prices bottomed out at the end of the last year, falling on average by 25 to 30% from their peak in mid 2007.
"Encouragingly, April has brought a significant increase in new buyer registrations – over 20% higher when compared with April 2008 – and this included the Easter holiday fortnight. April also saw an increase in first-time buyers, representing 45% of all new registrations.
"This has resulted in a 30% increase in the number of sales agreed over April 2008 and, due to the relatively short supply of new properties coming to the market, there is now upward pressure on selling prices.
"We are already starting to see an increase in both asking and selling prices and, based on supply and demand continuing at similar levels as seen during April, I believe we will see actual selling prices increase between 5 and 10% over the next six months.
"This will release many home owners from negative equity, increase the level of new properties coming to the market and ease the present imbalance between supply and demand.
"At the beginning of this year we predicted an increase of 10 to 15% in overall sales transactions during 2009. We now predict that this will be between 15 and 20%, although still almost half the number of transactions in 2007.
"These forecasts are converse to many institutions and market commentators’ predictions, and are supported by current activity levels across our network of London offices."
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