thank you for the advice!
Daily vomiting could be due to lymphocytic/plasmacytic enteritis, which is an inflammation of the GI tract, or it could be due to hyperthyroidism, heart disease, GI. parasites, some infectious diseases, and cancers of the GI.
Hyperthyroidism, bartonellosis and other infectious disease can be diagnosed by blood tests. Cancer's and heart disease can be diagnosed by X-Ray, ultrasound or echocardiogram.
Lymphocytic/plasmacytic enteritis requires a biopsy and endoscopy.
To save money your veterinarian could try a therapeutic trial with a steroid (prednisolone) and if it helps than your cat probably has lymphocytic/plasmacytic enteritis.
You could also try a low-dose of daily pepcid and anti-emetics (anti-nausea medications) such as Reglan or Cerenia (off label use), which are available from your veterinarian.
Symptomatic therapy may be all that she needs. Once the symptoms are under control with (for example), steroids and reglan, than the doses can be decreased to the lowest effective dose that can be safely used long term.
Other possibilities could include herbal therapy. Another posting listed listed the herbal preparation: Stomach Happy, from Jing Tang herbal company. This may also be effective for your cat.