New cases concerning house sales are also on the rise again.
Hamer said he expected these figures to grow still more later this year.
Hamer reports he is investigating almost 79% more lettings cases (127) at the moment than he did in the same period, July 1 to September 30, last year (71) although the number of people calling for help about lettings has only risen by 67% to reach 1679 over the quarter.
Cases under investigation involving sales have risen 17% for the third quarter, from 104 to 122. But reflecting market conditions they are still almost 32% below last year’s level (179) while inquiries are down by 36% over the year (966 in 2009, 1525 in 2008).
"The statistics in this report covering the period 1 July to 30 September 2009 show the continuing trend of increasing lettings disputes referred to my office," Mr Hamer said.
"I have noted, however, a small surge in sales disputes and whilst there has been much talk about the market beginning to pick up, if that is true it will be some months yet before that has an effect on my workload.
"Trends in the market are mirrored in the numbers of cases that I am asked to decide about three to four months later so any actual increase in activity in the market will become apparent in my workload towards the end of the year."
The principal causes of disputes over lettings arise when agents are alleged to have failed to make adequate checks of tenant references, not explaining that holding deposits are forfeit if the tenant does not go ahead with renting the property, and inspection visits not being frequent enough to prevent deterioration of the property.
With regard to sales, complaints have arisen from sellers who have been asked to pay for a Home Information Pack when the property has not sold and home owners who have become liable to dual fees after switching agents when the market was slow.
Related to this second point, Hamer reports he is also getting calls from estate agents complaining about the behaviour of other agents who are making unsolicited approaches to sellers who already have their properties for sale or to let, widely known as "touting".
He adds that the quantity and format of "flyers" put out by agents, whether targeted at a district, street, or individual addresses, could be an irritation to occupants. To comply with the Code of Conduct issued by TPO, any material should also fully explain to property owners that there is the risk of a double liability to fees if they are currently, or have been, selling their property through another agent.
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