It is a common myth that indoor cats need not be vaccinated but it is not as such. there are as much as 5 viral diseases including rabies that a cat needs to be vaccinated for irrespective of whether it’s an indoor or a stray cat. The vaccination process usually begins when the cat is 8 to 12 weeks old and the total cost for which varies from $100 to $200 depending on the pet but it’s totally worth it.