It all depends on who is teaching the course. Is it expected that you use shop sold gear? If so are they willing to supply it? I would not buy all new gear. That is assuming you already have everything. IMO anyone starting DM should already have all their own gear including at least 2 tanks. Some places reportedly won't let you around students(internship portion) unlees your gear is the brand they sell. This is BS. How long is the course? How flexible is the schedule? If all the others drop out for some reason will they finish your class? Expect some level of servitude. You will haul tanks, check in and rinse gear, shlep weights, deal with PIA people who have no business in the water in the first place. Be Nice to them. How much effort will you need to put into it? That depends on what you want out of it. As DM candidate I assisted with about 20 certs from ow to rescue, helped with a discover for a science class from a local college( 45 students over 3 nights broken down into groups of 5-6), did my mapping exercise over the course of about 15 dives(it's very detailed) with half of them solo. My course lasted nearly a year due to scheduling, shop moving, working friggin swing shifts etc. But I did get alot of experience with alot of different people in many environments.