Complex sentence: They were exploited by landlords and forced to pay rents that were two to three times higher than families paid in the more spacious white districts; and, like other poor migrants, they were generally limited to the oldest, substandard housing.
Split into simpler sentences: They were exploited by landlords and forced to pay rents that were two to three times higher than families paid in the less densely populated white districts. Like other poor migrants, they were generally limited to the oldest, substandard housing.