I totally forgot to answer your questions:
Money tips: If you can get into a program that helps to subsidize your food, travel, and lodging, that is a huge bonus. Most programs don't, but some (like programs with kids in very rural areas or national parks) may. AC helped me understand exactly what I needed to survive. Your stipend won't be much, so push yourself to just get basics. I moved to a farm and helped out there in exchange for cheap rent. And I paired down my grocery bill hugely. The cash restrictions will force you to get creative, and those skills will stay with you the rest of your life. Take advantage of the Education award--it is effectively half of your salary. Be warned, though, that if you go to use it for loans, it will be taxed as income.
As for poorly run programs, I have heard of several which are very disorganized. The two that I took part in were both phenomenally organized. Take a look at the organization they are supporting. I have found that the AC unit tends to be, in part, a reflection of their parent org. If that org seems steady and well-run, there is a good chance that they have taken the time to find a suitable supervisor.