This has been discussed previously. I have not done any. Perhaps others will chime in. One issue is that you go to a parking lot in the evening and cruise around trying to find the right kind of commercial vehicles, and then you record information about them. Two things then jump out at me. First, it might be very suspicious to be found cruising around a high end (I think) hotel parking lot, which may have an attendant. Be prepared to answer questions. Second, if you don't find the right kind of vehicles, you don't get paid anything for the time you spend looking for them. I am not sure that they even reimburse for the parking fees you might have incurred in that case.
Edited to add: You might want to re-post this in the Mystery Shopping Discussion area. My feeling is that a lot more people read that section, and your question is quite appropriate there.
Shopping Southeast Pennsylvania, Delaware above the canal, and South Jersey since 2008
Edited 1 time(s). Last edit at 04/29/2016 03:42AM by myst4au.