The scenario decides the draw, not the other way round
Most people start with a list of tests — CBC, lipid profile, HbA1c, vitamin D — and treat the home visit as a delivery problem. In practice it works the other way. Whether you need to fast, what time the nurse should arrive, how the samples travel, and how fast you get results all change with your situation. A cholesterol check needs an empty stomach and a morning slot; a vitamin D test does not care when you ate; an HbA1c for someone managing diabetes needs to land on a three-month rhythm, not whenever a slot is free.
One general rule before the scenarios: at-home phlebotomy is a collection service, not a diagnosis service. The nurse can tell you which tube is for which test; they cannot and should not interpret your results. That part belongs to a doctor, and we will come back to when that conversation is non-negotiable.