Brick and mortor ? What limit

I am itching to play hold'em in a Casino and my bankroll is Extremely limited!! $300. The 2 lowest limits that are offered at the Casino's by me (Detroit) are $3 and $6 limit and $50 minimum $100 maximum Buy in NL. My best game (online) is Sit-n-go's. Well I have heard that you need 200 times the big blind to play limit poker. That would be $1200 in this senario. Do I just go play the NL game buy in for the Max. $100 and take 3 different trips to the Casino or Do I use the $300 for the $3 to $6 table the first time I go and see what that gets me?

I would probably play the 3/6$ or buy in for $50 at the NL, but thats personal preference and probably not the best move. I'm guessing that buying in for 100 would technically be better but I wouldnt want to risk 1/3 of my bankroll possibly on one hand.

Build up your bankroll before you go. You never want to put yourself in a situation where you are putting so large of a % of your bankroll on one session/buy-in.