A: I’m pretty sure they give you a corporate credit card, with a limit. Maybe like $100 or something. (I really doubt they “take your money”.)
B: I saw a Mystery Shopper in action once, it was pretty awesome. I was at the LCBO, and this kid was standing so close to me in checkout. Anyway I buy my stuff, and this kid is walking right behind me without paying. This woman dressed in civies comes out of nowhere and is like “FREEZE”, and the kid drops this plastic of vodka out of his pants and bolts. She chases after him, and I’m like “WTF is going on?”
Anyway, good luck, it looks like an exciting career.