$899 Canadian so roughly $650 USD. What should I be looking for in a used unit?
Ah, that makes sense.
Compressors are pretty simple machines. If cared for they can last decades. The easiest thing is just let it pump up from empty and time it. You can use an online pump up calculator to see how much time it should take to fill from empty. If it's close to advertised, it's at least functioning properly.
If it's got motor trouble, or valves are shot, or is leaking, it won't be able to make near its advertised output. Assuming you don't want a project, you could just move on.
About the only other thing to easily check would be to open the drain and make sure it hasnt been sitting with a bunch if water in the bottom of the tank forever.
If you're willing to spend the equivalent of $650 plus tax, you could probably find a nice 15+ cfm 60 gallon used. On the other hand, if 11 cfm is enough air for your purposes, you could just pick up the subject machine and be done with it.
