Before I book a Jeep inspection, what am I actually paying for?

I'm looking at a used Grand Cherokee and I've finally convinced myself to get it checked before buying, but now I'm stuck on the details. I keep going back to the same Jeep inspection page and honestly every time I read it I notice something I missed the first time, so I keep having to see more about what the different packages actually cover before I commit to a booking. My worry is that I'll pay for a basic check and then find out the thing I'm most nervous about, the air suspension and the electronics, wasn't even part of it. The seller seems decent and isn't rushing me, so I'd rather take an extra day to understand what I'm getting than book the wrong thing. For those who've had a Jeep checked before, did the standard inspection cover the stuff that actually matters on these cars or did you have to ask for extras? I don't mind paying for a thorough job but I hate the idea of paying for something half done.