Re:B&B in PV
To add to Casa Corazon, I have stayed there as well. It is on the southside of Los Muertos- quite far from the Church.
It is very very basic, not what most people would think of as a bed and breakfast (as they tend to be more boutique hotels)- and this is classic Mexican style with little amenities. In the low season, it is very economical and in a great location. In the high season, the prices compare to the Tropicana which is ocean front, pool, A/C restaurant, etc....
Villa Bella is up the hill in La Cruz de Huanacaxtle, about 45 minutes from Puerto Vallarta- about 10 minute walk to the beach.