Check at your local pet shelters for information. Where I live (Akron, Ohio) there are low-cost shot clinics available. There is also a list of veterinarians who do low cost neutering and spaying. My son had his puppy neutered for only $40.00.
Even if you keep your dog in a fenced area outside, you need to watch out for other animals getting into your yard, that could be harmful to your dog. Cats can get over fences and feral cats can carry who-knows-what. We live in the city and we still have wild critters here. Posson, raccoons, skunk. So my son is very careful when he lets the dog outside.
My son buys the big bags of dog food – he like Beneful – at BJ’s Warehouse Club. It’s cheaper than other stores, and BJ’s sends a flyer with their coupons and accepts manufactureres’ coupons as well and that bring the cost down even further.