Needing a vitamin deficiency test done what are the main most important vitamins i should get tested for? who gives these tests & what does it cost?

Depends: Any knowledgable doctor can do these tests. I do extensive vitamin and mineral testing routinely for my patients. An integrative medicine physician would be a good bet, especially one who does orthomolecular medicine. Many tests can be done through labcorp or quest, and may be covered by insurance. I test b vitamins, zinc, copper, rbc magnesium, and more.