I know, first hand, that they offer spay and neutering for cats, pit bulls and Chihuahuas (these are the top breeded animals in SD County) for "free". Appointments can be made for the weekend. You are still subject to disposal and medication fees, which total no more than $80.
They will spay/neuter your pet if you qualify for their low income program. Call them and they will let you know.
If you are low income they do have a spay neuter program for free. However, if animal is older they do require a blood test that you can only get at a vet and you have to pay for that.
They spay and neuter all pets before adoption, but I do not believe they spay individually owned pets, but I'm sure they can steer you towards low cost options. It's best if you call to verify.
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