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Yet another may have been a reduction in the real-estate listings and property-related financial services (such as mortgage loans or insurance policies) offered in some areas of the Bronx a process known as redlining. Others have suggested a "planned shrinkage" of municipal services, such as fire-fighting. There was also much debate as to whether rent control laws had made it less profitable (or more costly) for landlords to maintain existing buildings with their existing tenants than to abandon or destroy those buildings.

What might have encouraged landlords to abandon or destroy buildings?
rent control laws