I will only do the drive-through, not the drive-in. They always want to know exactly, like to the second, how long it took to do various aspects of the shop. For the most part, I will remember what time I pulled in and what time I left. Whatever time has elapsed, I will just break that into estimated increments. The receipt always has a timestamp on it so that helps divide up the time intervals.
I just did a sonic shop two days ago, and I tried using my stopwatch on my iPhone where I hit the interval button every time a shop event happened. That wasn’t too obtrusive and it kind of made it easier to piece things together.
There is a sonic less than a mile away from me and I tend to grab the drive-through shops only because you gotta eat something so I might as well eat for free. They are not my favorite, though, and I would never go there if I was paying out of my own pocket because there’s many other options also within a mile. This is the kind of shop where it’s nice because you can do a lot of them and once you’ve done a few, it is easy to remember what needs to be done. Aside from the very specific timing breakdown, the requirements are actually pretty minimal.