Balancing is highly overrated. As long as you are not flying Extreme Speed planes, don't worry about it. I fly with prop sizes ranging from 9" to 22" (Mostly 11" - 14") and in over 40 years of flying I have balanced 3 props - and I only did those because a girlfriend bought me a Balancer for Xmas one year so I felt obligated to use it.

There ARE times when balancing is important - even critical, but flying you basic trainer or sport plane isn't one of them.