Based on your academic credentials, financial requirements and location you would have chosen a few universities and marked them safe, ambitious or moderate depending on your chances of admission to each. 5 ambitious, 3 medium and 2 safe schools is what students usually go for while applying to study in the USA.
However, given the current competitive scenario, be sure to revisit your shortlist with due research on past GRE scores, your academics, and if required, go for more safe universities to ensure some admits.
If applying to multiple universities is proving heavy on your wallet, then make sure to complete safe and moderate ones first.