I preform this USPS shops all the time. I found the way to protect yourself, is buy something from the store that is that weight. Like I send pinto beans, rice, stuff like that to a friend. It's super cheap to buy, it never waivers as the weight.

What I have found from all shops in general, they say over and over again in the shop details to read and follow directions. I have lost pay on shops for simple thing I over looked, a picture of a specific item, an extra phone call I did not make. What they want is for us to follow the rules regardless, I think, it makes them think we have actually read all the paper work they give us to go through before the shop.

Just my thoughts. Good luck everyone.