Pamela DeLorme, the principal in Delkap Management, has learned how to juggle personalities in the 28 years her firm has been managing the Northridge Cooperatives, a six-building, 400-unit complex built in Jackson Heights, Queens, in 1948. The property — like the neighborhood, a "cultural melting pot," according to DeLorme — has transformed from a mostly Orthodox Jewish enclave to one that features a mix of cultures and age groups. The neighborhood has always been attractive to families because of its easy access to stores, supermarkets, restaurants, religious venues and schools.