[anonymous]

Examples for low cost veterinary care
http://www.humanesociety.org/animals/resources/tips/trouble_affording_veterinary_care.html
http://aapaw.org/resources/vet-assistance-programs.html

Present the vet with a list of your dogs symptoms, how long they have been going on.
Veterinarians have examined thousands of dogs and will be able to determine which tests need to be done immediately. (labs, x-rays and such) Treatments such as subq fluids may be indicated if your dog is dehydrated (caused by excessive vomiting)

When a diagnosis is determined, the vet will discuss treatment options with you.

Discuss your financial concerns with the clinic and they will explain your options.