Manhattan has more open residences now than at any time in the past nine years, but median rent prices continue to increase.

The vacancy rate in Manhattan expanded to nearly 2.9 percent, the most in more than nine years, according to the newest Douglas Elliman Report. The median rental price increased 3.9 percent to $3,361 from the same month last year. Rental price per square foot averaged at $52.45, the report also stated.

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While key demand indicators, such as tight credit and a strong citywide economy, haven’t changed, declining affordability may put the brakes on the price gains rentals have seen in recent years, the report stated, adding that some market weakness was appearing, such as an increase in landlords paying brokerage commissions and offering tenants deals such as free rent.

In Brooklyn, while rental prices continued to approach recent records, the rate of price growth eased, according to the Elliman report. The rise in median rental price has lessened each month since August, when rental prices peaked. Median rental price slipped to $2,935 from the same period a year ago, approximately a half-percent drop.

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In northwest Queens, the median rental price moved higher to $2,735, but the number of apartments where landlords paid brokerage commissions and provided free rent accounted for more than half of all transactions, the report stated. Those increases were most apparent in the studio and one-bedroom markets.