Protocol for doing business/running it twice

[Dahveed]

I'm taking a trip to Vegas soon, but given that I don't get to play often I'd rather lower my short-term variance in certain situations.

To that end, what exactly is the protocol for asking a player if he/she wants to run it more than once? If you are betting, do you say then? If you are facing an all-in call decision, would you ask before or after making the call? If in both cases you wait until betting has been concluded, do you simply ask the dealer to wait while you confer with your opponent?

Also, do stakes matter? In terms of NL, I'd only be playing $1/2 unless I start running really well - do casinos frown on this in low-limit games? Any responses will be much appreciated