Pet Shotz will do it for free if you're in a certain zip code. The cost I paid was very low compared to 4 to 6 hundred dollars at regular vet clinics
Pet Shotz offers $25.00 spay and neuter for neighbor hood cats. Let them know they are strays and not your cats. Includes rabies shot. Anyone qualifies for this discount.
You have to fit the criteria for free service otherwise it's at a discount. Nevertheless it is still worth investing the time as it will take all day. But I do not believe the discounted price can be beat or matched anywhere. And if you do find someone that beats it please post the information!
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