Our vet recently suggested some very pricey tests for our cat when she was sick. The tests alone were over $800, and then depending upon what they found, it was just going to go up from there! Well, we did not have an extra $800+ earmarked for the cat's vet bill, that's for sure, yet she is a beloved pet and I wanted to help her. So I thought about it, and then asked the vet to sit down and discuss the tests with me. I asked him, bottom line, what's the list of stuff that could be wrong with my cat? Once we had that on the table, I asked what the treatment plans would be for each of these illnesses. The plan seemed to be antibiotics for everything, so I asked if we could skip the $800 in tests and just go straight to antibiotics. I think vets must make a ton of money on tests, because he seemed kind of bummed out that I didn't want all these tests, but he agreed that if the treatment was exactly the same, then it was stupid to test for everything. So I took the antibiotics home, gave them to the cat, and she got better. We went back for a follow-up visit and she was fine.
So my point is, just because they tell you it's going to cost you a fortune, you still have options. Ask why they need to do all these things, go over the itemized bill just like you would for your own medical issues, and make sure everything is legit. Realize that you can ask for discounts and sample medications just like you do at your own doctor's office - the worst they can say is no. There are ways to economize. Also, don't be afraid to shop around! If you know what's wrong with your dog, call a few vets and ask what it would cost to have the surgery at their animal hospital. Some vets are WAY more expensive than others.
I wish you the best of luck, and I hope your doggies get better soon!