A good dance school doesn't have to cost you a small fortune. Compare what several dance schools provide. Also find out if they have a personalized payment plan that you can use. Or, look for a small, privately owned dance school that can give you individualized attention for less.
Good communication is key to success in any school, including in a dance school. For this reason, evaluate how well the dance instructors are organized and how well they communicate information, movements and corrections to you. This will determine the success you see and feel.