table buy-in amount

I am going to start playing $1/2 on PP and i was wondering what the standard buy-in is for those limits, and what are the standard buy-ins for $2/4, $3/6, etc? Is there a general set amount like 50x the big blind (25x big bet)?

[shant]

Party's standard buy-in is 25 big bets. So for 1/2 it's $50. Some people like to buy in for more. Anywhere from 25-50BB should be fine.

[SavageMiser]

I like to buy in for about 40 BB. Makes it easy for me to implement the -30 BB rule (even if a game appears good, if I lose 30 BB in a session I'm probably not playing well so I should leave) because if I drop below 12 BB, I know I've reached my leaving point.

Or is that too complicated?

no, thats great. thanks!