Importers: what's the worst customs/tariff surprise you've ever had?

I built Zentria Flow because I kept seeing the same thing: importers price a product off the supplier invoice, then customs hits — Section 301, IEEPA, VAT, fees — and the real landed cost ends up 30–145% higher. Most duty calculators only show the base rate, so the gap blindsides people at the port.

So I'm curious — for those of you who import (China, Vietnam, anywhere):

• What's the worst customs/tariff surprise that wrecked a margin?

• How do you currently calculate your true landed cost — spreadsheet, broker, gut feel?

Zentria Flow stacks every layer (duty + Section 301 + IEEPA + VAT + freight) for 70+ countries in seconds. You can try it free, no signup:
https://zentriaflow.com/customs-duty-calculator

Happy to run anyone's product through it and share the breakdown — genuinely curious if our numbers match your real-world experience.

Would love to hear your stories. 👇