Retailers previously priced out of Soho and the Upper East Side are taking advantage of falling rents and opening shops. Rents in the city fell an average of 11 percent between fall 2008 and spring 2009, Crain’s New York Business reported. Soho and Nolita are expected to see the biggest drop in rent this year — about 20 percent. Shoe store Camper recently signed a one-year lease on Madison Avenue at 59th Street for about $500 a foot, and thrift shop Housing Works just opened its ninth location in the city on Crosby Street in Soho. In addition, sneaker store Flight Club just leased its third Manhattan location on Lafayette Street for just $70 a foot. Brokers said the space could have fetched $200 a foot last year.