I also play these low limit games and managed to build my bank roll up to about $150 from a starting bank roll of $10 in about 6 days purely from money finishes in 9 and 6 seater STTs and the odd MTT money finish here and there. My bankroll took a dramatic nose dive last week when I entered a MTT after MTT only to get knocked out just before the money by fish and calling stations. My bank roll plummeted to just over $1 by last Saturday so I now have the task of starting from scratch. Its up to about $6 after 3-$1 STTs so will stick to $1 for the time being until it gets to about $44 then I'll move up to $2. This would give me about 20 attempts at $2 STTs before going bust. My money finish rate is quite good at these low limits so I'd be looking to finish in the money 7 out of 10 games.
I hope my way of managing a tight bankroll helps you to find your system.