Being presented with a sealed envelope poses a bit of a challenge, doesn't it? It seems to me that most ladies would prefer to get an unsealed envelope, so that's how I leave it.
If the client gives you a sealed envelope, I think it's more likely that they are short changing you, and betting that you won't want to tear it open.
If it's sealed, I'd suggest politely asking the client to open it (not you) so there's no mistake and accusation that you slipped out a bill. If he won't open it, or makes a fuss ("What, you don't trust me blah blah blah") then I'd bet that you are getting ripped off... An honest guy would have no problem opening it, and would likely apologize for the inconvenience.
If the client gives you a sealed envelope, I think it's more likely that they are short changing you, and betting that you won't want to tear it open.
If it's sealed, I'd suggest politely asking the client to open it (not you) so there's no mistake and accusation that you slipped out a bill. If he won't open it, or makes a fuss ("What, you don't trust me blah blah blah") then I'd bet that you are getting ripped off... An honest guy would have no problem opening it, and would likely apologize for the inconvenience.

