What does a product audit involve?

Not sure. Do you have more details?

Usually checking to see if products are available in store. They can be very time consuming if there are a lot of products to look for.

I've been wondering how long an audit would last...some say there are over 100 items to scan.

If you're talking about the Costco product audits, the training materials said when you're doing your first audit, you can expect to spend a full 8 hours there scanning. Then, supposedly, you get used to the app and can complete the audit in 4 or 5 hours. But you have to scan so many items, without being noticed, and I've read on other forums and reddit that some people are getting kicked out when they're discovered. Because it's basically impossible to scan hundreds of items for hours straight without looking suspicious.