I've been at this since Aug 2021 and figured out a routine after driving myself crazy (a touch of OCD of not knowing what to really expect). Like many of our colleagues, I figured out system that works for me. As someone else suggested, accept only 1 shop of a given type (ie. 1 big box hardware store audit) to see it it is worth the effort; then sign up for the remaining in the area. The other part of the system is to know what price point is worth the effort; and that holding out until later in the month typically gives you bonus pay.
For tracking, I use a spreadsheet (MSC, merchant, location, brief description, amt, reimbursements, non-reimburse expenses, mileage, expected pay date, actual date paid, amt at risk <purchase or other expenses to be refunded>
. I have a color code based on the stage (item not received, return processed pending refund, pending review/approval, future scheduled shop). To be extra OCD, I have pivot tables summarizing the data.
During the shop itself, I finally wised up and take my iPad with me. I'm able to complete the shop in "real time" using my hotspot or coffee shop wifi. I found writing the information down to then type it into the shop a waste of time and I always forgot something.
For example, if you forgot a picture and you can go back & get it easily (unless the editor is reading the pic's meta data to get the timestamp - tip remove the metadata unless the shop specifically calls out that you need to have it visible in the picture, been there done that).