I posted an item I was selling on Craigslist. This is two different buyers who want to buy my item. One was $150 and the other was $100. And these two separate buyer had sent me a check that was over $1000. I checked my email to inform them then they had said the EXACT same thing. They both wanted me to run by the money gram and send the rest of the money to some person’s address (two different person’s address). I already know that this is a scam; what should I do?
Shred the checks and report the buyer as a scammer. There is absolutely no chance this isn't a scam. It follows the formula to the letter.
Craig's List has a page of how to report scam attempts.
The above page even describes this scam:
2. Distant person offers a genuine-looking (but fake) cashier's check:
You receive an email or text (examples below) offering to buy your item, pay for your services in advance, or rent your apartment, sight unseen and without meeting you in person. A cashier's check is offered for your sale item as a deposit for an apartment or for your services. Value of cashier's check often far exceeds your item—scammer offers to "trust" you, and asks you to wire the balance via money transfer service. Banks will cash fake checks AND THEN HOLD YOU RESPONSIBLE WHEN THE CHECK FAILS TO CLEAR, sometimes including criminal prosecution. Scams often pretend to involve a 3rd party (shipping agent, business associate, etc.).