The Spartan has a lot going for it apart from cost, you can fit a GPMG, it's not a Rareden cannon, but it is a gun, easier to work on that a Scorpion, Scimitar or Sabre and has a lot more room.
You need to factor in not just the vehicle cost but fuel, insurance, recovery, spare parts, oil, filters as well as spares availability, and of course if you need a licence to drive a tracked vehicle the cost, if you do not already have one, of that. The other little issue often overlooked is of physically getting into and out of a CVRT, which for some people is impossible.
Diana