We return to the James Cayce Homes to follow up with residents amid the $600 million overhaul. But in checking back, we trip into some news. And we’re reminded, yet again, of how difficult it will be to pull off this massive redevelopment. As the city preps to turn its largest public housing projects into a mixed income development, Cayce residents have to sign a new agreement with steeper fines for late rent, stricter limits on guests and cleaning rules. Plus, higher income tenants won’t have to sign it, which is making residents all the more skeptical, casting doubt on whether the housing authority can really deliver on its promise: To build a community where both the city’s poorest residents and prosperous city-dwellers can live in harmony.