Try finding low cost vet services in your area. In Austin, Emancipet will spay or neuter you pet for free if you live in a certain area. They also provide many other services. Their web address is www.emancipet.org.
There is a no interest credit card available to help you pay for veterinary expenses. It is called Care Credit. Make sure your veterinary provider selects the no interest option when they swipe your card. One card works for the whole family. Unlike other credit cards, your minimum monthly payment appears to be high enough to ensure your balance will be paid in full before the interest free period ends. Care Credit also works for other medical expenses. Visit their website www.carecredit.com to find out more.