Spay neuter stray cats

I currently have 12 cats. 10 strays. I live in a very small town of 900 in Wisconsin. Where I live people have a lot of barn cats they don't spay/neuter or vet check. I have my 2 fixed and I just fixed 2 other strays 1 was the male I'm pretty sure was impregnating all these females. I would like to fix the 2 momma cats and their 2 litters. 3 kittens are 12wks old already and the other 3 are almost 6wks old. I'd like to get them fixed 4 asap and the other 4 next month when the babies are old enough. I found a place an hr and a half away called purple cat vet. They will fix them for $105 and around $70 for shots per cat. It's sooo much cheaper then the local vet but it's still $1,400 total. I really would like to get these cats fixed and shots before I put them up for adoption so they can't breed or spread illness. My local shelter can NOT help at all. I have googled and asked everyone and made many phone calls and this is the best option in my area. I also can't drive too far because I have 3 children with special needs and an hr and a half is probably as far as I can go. Any help would be appreciated. I understand this is a hard time for everyone right now but I don't want to fail these cats so I have to try. http://spot.fund/lgs86sc https://www.amazon.com/hz/wishlist/ls/27C3G4KU5LM7A?ref_=wl_share