Good luck with any of them.. I've been getting numerous tests done for the past half a year and they all keep coming out clean even though I am sure I have candida. Been reading it doesn't show up well in tests, and western practice doctors aren't even trained to acknowledge it as a condition unless it's a vaginal yeast infection or oral thrush where there are visual signs. I'd try the natural route if you suspect you have candida. First change your diet (no sugar, no wheat, very low carb, etc- read online) and see if that helps. If so, try a natural route through an alternative practitioner such as an herbalist.
Best of luck to you!
I feel the stool culture is the best as Candida usually lives in the digestive tract and can be detected in the stool easier than blood work.