I did one of these a while back. It involved opening each cooler door in the c-store that had sodas/non-alcoholic drinks and taking two or three pictures that covered the stock inside. There were additional questions about the sodas that were stocked outside of the coolers. If the c-store was empty, it was a little weird, but no employee ever came over to see what I was doing. It wasn't too hard. The type of shop that I did took about 20 minutes from start to submitting the results.