Win Limits
First of all I believe that your bankroll must be at least 30-40 times the table minimum, so that you can get through a bad run. I have found that 'flat bets' are the best. Wait until you get the advantage (splits and double downs) to increase the bet. A $10 bet will become $20 or more. Let me give you an example. When they put a new deck in play, you are a slight underdog 101-100. You bet $10. If you are delt an 11 against the dealer 10, you suddenly become a 6-5 favorite. You should always double. Don't start out betting $20 dollars, only to find the dealer has delt a blackjack for themselves.
As for limits,starting out with $50-$70 dollars, playing on a $5 minimum table, anything is possible. There is this thing in gambling called LUCK. Luck is always better than knowing how to play. You see it all the time. Some clown doubles 12 vs a dealer 10 and wins.
Realisticlly, if you could double your money, I would start putting some in my pocket. Most people set their win limit so high compared to their bets, they never achieve it and wind up losing everything.