Neutering your pet prior to maturity and spaying your pet prior to her first heat cycle (both at 4-6 months old) offers the best protection against serious health issues and the establishment of negative behaviors.

Low-Cost Spay and Neuter Programs

Arizona Humane Society
Animal Defense League (ALSO FOR FERAL CATS) 602-265-SPAY
SpayAZ (ALSO DOES Vaccines, Microchipping, Testing) 866-952-SPAY

Low-Cost Vaccinations

VETCO at PETCO
Services: Vaccines, FeLV/FIV testing, Microchipping, Basic examinations. Phone: 1-877-VET-SHOT

SpayAZ

Services: Spay/Neuter, Vaccines, Microchipping, Testing, 866-952-SPAY

Low-Cost Vet Clinics and Emergency Clinics

The following link gives you a list of organizations that may be able to help you with vet costs if you qualify.
Phoenix Animal Care Coalition

Veterinary Cost Assistance Programs

Need help with your veterinary bill? Accidents and illnesses can be expensive, but all pets deserve to receive the medical treatment they need to live a pain-free life. Red Rover has a program that helps with vet costs plus has a list of other programs that help with veterinary care costs if you qualify.

Care Credit: Provides credit for vet bills.