Just throwing it out as a restaurant owner - there’s not a lot of people that do this even though its usually required by fire codes. I had to call around multiple places before we finally found someone in the beginning. That’s a good thing though because you can probably get business pretty easily.

• Expect to work unfavorable hours when restaurants are closed. Nights and weekends.
• Don’t leave a massive mess. It’s a messy job, but clean up after yourself. Leave it how you’d want your mom or dad to come in to find it afterward. You’d be shocked just how far that will get you in positive word of mouth.
• Be proactive with planning. I forget to schedule it all the time and you can get additional steady revenue by just reaching out to remind people to schedule it.
• Some places don’t want you to use their water. I don’t know why. Most providers will bring a water tank. If you don’t want to buy a tank, make sure you can ask if you can use their water and where the access points are.
• Do what you say you’re going to do. Show up when you say you’re going to show up. This puts you ahead of 90% of the competition (and the same goes for any contracting service).
• Expect people to jerk you around over payment, especially if you’re young. We always pay same-day, but we are the exception - not the rule. Get signed quotes upfront that spell out payment expectations.
• Get insurance. Restaurant hood systems include automatic fire systems with some pulleys and pins in the hood framework. If you were to set one of those off cleaning, its thousands of dollars and days of lost revenue for them to reset. They’ll almost certainly be going after you for it.