What do you wish you knew before studying at a language school?

I'm planning to enroll in a language school next year in order to improve my resume (I want to work in a field that requires better Japanese literacy than I currently have). I have a trip lined up soon to visit a few campuses in person, and I wanted to crowdsource some questions to ask the staff/school representatives during the visits. So far I have:

  1. Typical ages and nationalities of students
  2. Teaching philosophy/approach (I'm particular about what kinds of approaches work for me)
  3. Whether they issue a diploma, certificate, or similar upon course completion
  4. Support for various things related to residency and the JLPT
  5. How long it typically takes for their students to reach N3/N2/N1

Let me know what other bases I need to cover in my questions. In case it's relevant, I'm specifically looking at Akamonkai, ARC, Intercultural Institute of Japan, ISI, and KCP. Thanks in advance!

by IamAmadeusRex