Simplified Geography: 

To keep things simple, consider the Area of Puerto Vallarta to be the beach side towns on the Bahia de Banderas:

Puerto Vallarta, Nuevo Vallarta; Bucerias, La Cruz De Huanacaxtle and Punta de Mita.

We consider the Area on Riviera Nayarit to be the seaside towns on the Pacific:

Litibu, Sayulita, San Francisco, Lo De Marcos, Punta Raza, Los Ayala, Guayabitos, and La Peñita.

Bucerias
Cruz De Huanacaxtle
Nuevo Vallarta
Puerto Vallarta
Punta Mita