Tyler,
Another issue is the hose size and type. I believe my CT22 came with a 27mm antistatic hose that was 11-1/2 feet long. However, that does not mean that a used one will come with the same hose.
I also have several antistatic hoses - several 27mm, one 36mm, and one 50mm. And one 36mm non-antistatic hose. I've modified several of my hoses for different reasons - creating an adapter hose, repairing damage, etc. And I don't use the non-antistatic hose because the static attracts dust. (I used it on my Kapex for a long session and it looked like a fuzzy snake.)
The point is that the hose (or lack thereof) that included with a used CT can greatly affect the value, especially if you need a 36mm or 50mm hose antistatic hose. For example, if there is no hose or the hose is damaged, the most inexpensive, base 27mm 11.5 ft hose is $115.
Good luck with your search.
Dan.