You can see if you know anyone in san Antonio city limits who lives in a qualifying zip code and use their address for petshotz or the humane society.
Pet Shotz by the zoo
No chance of free but I used Snap on 410 and Ingram it is nonprofit. A spay for dogs under 35 pounds is only $81
ACS is only for San Antonio. Contact your local shelter for advice. Some rescues may know of resources outside of San Antonio.
Medina isn't even in the same county. So no.
Is Medina outside of San Antonio? If it is you'll have to look in your local area. ACS doesn't provide free services like that to people outside the city limits. You could also call them as well.
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