By Cherri Gregg

PHILADELPHIA (CBS) — A coalition of affordable housing advocates issued a report this week on gentrification in Philadelphia. They want City Hall to tax developers that flip houses.

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Titled, “Development Without Displacement,” the report takes a dive into North, South and West Philadelphia – areas rife with development and where housing prices are doubling and tripling as thousands move to the city from the suburbs, pushing people of color out of the neighborhoods in large numbers.

“This is a cost that our city cannot bear. We need our neighborhoods to be strong, we need our neighborhoods to be diverse,” says Nora Lichtash, part of the steering committee of the Philadelphia Coalition for Affordable Communities which includes more than 35 organizations.

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Their solution: target developers who buy houses and sell them in less than two years by imposing a 1.5% tax on the second sale.

“Our city could raise 12 million dollars a year,” Lichtash says.

This is money, Lichtash says, that could be used to keep low income people in their homes.

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“We’re not against development,” says Lichtash, “but we don’t want this to push current residents out.”