Sorry if I repeat, but I haven't read all the posts. I don't know anything about the Cushings, but if spay/neuter is too expensive for them, they should go to
www.friendsofanimals.org. They can look up vets in their area that will accept a low cost spay/neuter certificate from Friends of Animals, purchase the certificate through the website, receive it in the mail and get their pups the spay/neuter they need. They should call the vet clinic first to verify that they still accept these certificates. For my area, they charged $90 for a spay, and $64 for a neuter.