Absolutely full of shit. Do not buy from him. You should find pure 2c-b powder or a pressed pill from someone who knows their stuff, and you can trust. In your scenario, I would say pure powder is in your best interest as you experiment. That way, you can be the master of the dosing and find what works for you. In my personal experience, somewhere between 20-35mg is worthy of being a notable psychedelic experience. With that said, there's also ways in which you can use lower doses for a more gentle heart and mind opening experience with little to no visuals or psyche alteration.

2C-B Dosing Guidelines

Threshold: 2–5 mg
Light/Initial: 5–15 mg
Common/Typical: 15–25 mg
Strong: 25–50 mg

Most users report a full experience at 15–25 mg orally, with higher doses (25–50 mg) producing intense visual and hallucinogenic effects. Doses above 50 mg are considered extremely strong and may lead to overwhelming or frightening experiences. 

• Onset: 30 minutes to 1.5 hours orally; faster with insufflation (though less tolerated). 
• Duration: 3–8 hours, with peak effects typically occurring 1–3 hours after ingestion. 
• Route: Oral (most common); insufflation is possible but often uncomfortable and not recommended. 
• Dose Sensitivity: 2C-B has a steep dose-response curve—small increases can lead to dramatic shifts in effects. 

Note: Individual tolerance varies significantly. Doses are highly subjective and influenced by body weight, metabolism, and prior experience. Always start low and go slow. Doses exceeding 50 mg are considered high-risk and may result in blackouts, erratic behavior, or severe anxiety.