They do cheap vaccs and meds.... I wouldn't recommend them for regular care as they are just processing animals and it benefits a dog being seem by a real vet, but it's better than nothing. I take my rescues there before I rehome them sometimes.
While he'll need to go into the vet for his rabies shot you can worm him and do the other shots yourself if you're comfortable with it.
You can pick up piprazine at the feed store for the roundworms. last time I bought it, it was around $5.00 for a bottle that I've had for a few years now. He should be wormed every 7-10 days until he's around 12 weeks old.
Some feed stores also carry shot packs that you can give yourself so call around, the shots aren't inexpensive, but much less then a vet visit.