You will get returns. It's a fact of e-commerce. The question is, how painful will it be?

Ask the supplier:

• What's your DOA policy? Do you replace units that fail within the first 24 hours?
• Do you provide batch numbers so I can verify authenticity and track issues?
• What's the process for handling customer complaints? Do they offer tech support?

If a supplier won't stand behind their product, that's a huge red flag. You don't want to be the one explaining to a customer why their vape died after two days and you can't offer a refund.

Also, think about your own support. Do you have a clear return policy that's fair to customers but doesn't drain your margins? Some stores offer a 30-day replacement guarantee. That builds trust, but you need the supplier to back it up.