I got a letter in the mail with an Ontario address. The company, JMK Value Added, was located in NY. Oddity #1.
It enclosed a hefty check with instructions on what to do with it. One had to activate the payroll check first by calling (huh?) and then call the "manager" as soon as I do the money wiring. Wire two big chunks via Western Union (big red flag), evaluate customer service, and then spend a little at a big box store, then keep the rest. $350 was my "salary," whereas most mystery shopper jobs pay about $20 per job (variable, but according to Mystery Shopper's Association, it's usually something in that league).
Something didn't add up. And the icing on the cake-atrocious spelling and grammar. After a little investigation, it turns out this is a nasty scam that can run your average Joe $3000-$4000. Basically when the check is processed, fraud goes undetected for weeks in most cases, and the account holder (you) are held liable for funds withdrawn against it. OUCH! I shredded the check without cashing it.
I dodged a bullet here, but I figured that this information might spare someone else from this nasty scam. If you get an unsolicited "job offer" and a check, it's too good to be true, and shred it. DO NOT cash it. Here's some details on it.
http://www.consumer.ftc.gov/articles/0053-mystery-shopper-scams