Craigslist transaction went south...

In followup to jmcgrogan2's post, the situation of someone receiving working equipment but then claiming it was defective by swapping in another similar but nonworking item can easily be avoided.  Every sale should include a bill of sale to prove legitimate purchase.  The bill of sale should include the item's serial number or other identification.  If the transaction is face to face, as was the OP's, then the seller should bring a copy of the bill of sale and have the buyer sign it as a receipt to be kept by the seller.  If the transaction is by mail, the bill of sale can be included in the box.  In addition, the seller should take pictures of the item to show its physical condition in case of dispute about that, and one of the pictures should be of the serial number.

I don't have a bill of sale. Even it he brings his broken one, I am going to give his money back as Dave and Rich said  "It Is not worth the hassle." 

Sorry to hear of your bad experience. I have not used CL much for 'gear'..but mostly old furniture, vacuum cleaners, etc. 
But did sell 2 older but well working TVs with no hassles at all.

Funny thing about CL the safest deals usually involve the most money, cars & trucks. In most cases once they agree to buy the car, you can do title changes and money transfers inside your local bank in front of witnesses. 

You do have more protection selling on ebay. You can even click the square that says, "Local Delivery Accepted". That's where I sell most of my cheaper electronics. You do have to deal with fees, etc. but if you plan well can do well.  I've purchased some nice things too. Of course, Audiogon and US Audio Mart are other options with low overheads. 

Cash and carry. Good for you! this guy (tire kicker) needs to realize these things are sold as is no warranty and for $120 good luck finding a lawyer for less than a $1000 too take up his lost cause! You did the right thing collecting the money and not letting him pay with a CC or Paypal. He has no leg to stand on!  I would not loose any sleep over this "wanna try it and return it guy" Heck with that!