Choosing the best logo for your accounting firm depends on your brand message, the niche-market you are dealing with, and the company set up you've got going on.
If you are a startup and catering to home-based or small to medium personal finance, your accounting logo should be simpler, with an accessible feel. For example, a piggy bank symbol, or a dollar sign with arrows around.
If you manage high finance or provide accounting services to more established and big businesses, go for a more professional logo such as logos with bar charts, or arrows and line graph logos.