In one area that once housed 496 families, more than 350 have moved, The Daily Telegraph of Britain reported. Payments for their houses, often shacks cobbled together from scrap iron, have averaged more than $160,000.
The area is close to the heart of India's financial capital.
Abdul Rashid, 58, now the owner of an apartment in a suburban building, said he wishes he had held out longer.
"Mumbai is growing at such a rate that I regret selling when I did," he told the newspaper. "I should've waited and demanded more money and then I could've got a bigger flat."
But Lubna Mamin, 23, who lives with her husband and his parents, says she is glad to have a home where she feels safe and indoor plumbing. In her case, the family accepted ownership of the new apartment in exchange for their shack.
Sarah Pravin, 43, is still holding out. She says the neighborhood has gotten even scarier as criminals move into buildings that have been emptied.