Idk about the CBD because the isn't many studies on its phamacology effects. But "buy the pure isolate and vape that" is a smart move to avoid dodgy products. Just be aware of the dosage.
I found this on mayoclinic: "Currently, the only CBD product approved by the Food and Drug Administration is a prescription oil called Epidiolex". You can look into this product to estimate a safe medicinal dosage.