I recently decided to follow through with a CL check-based scam, just to see how it goes (up to the point that it costs me anything, obviously).

First I got a text, from someone using an email-to-text service, inviting me to email them. I was then asked for an address, and actually got a check in the mail! Surprise surprise it was for more than my asking price, and I then got an email asking me to pay the "movers". I tried a little reverse scamming:

Thanks for getting my check to me so quickly. I took it to my bank yesterday, and they said that there wasn't enough money in your account to cover the full check. Apparently your account is $75 short. I'd like to finish this transaction, so here's what I am willing to do: if you send me the remaining $75, I will proceed to cash the original check, as the bank said they are able to give me the rest of the money. I would prefer the remaining $75 to be sent by cashier's check.

No dice though.

I then "lost" the check, and after a half-hearted follow-up from the scammers, they gave up on me.

The interesting thing was that each stage of the scam was apparently operated by different people, who had no idea about the rest of the transaction. I tested this by raising the price with every email, until my $200 item was $1000.