Used CTL maintenance hours/ issues

[Maloneyy042]

I am looking into purchasing a used CTL for use on my farm ( moving dirt/ Bush hogging) and I am looking for guidance on what hours is reasonable for purchasing and what are the hour/ usage benchmarks. What are things that need maintenance around certain hundreds or thousands of hours and what are systems that will me to be replaced as well. For example I know that file and water pumps on trucks will be needing to be replaced around the 120,000 mile mark, etc.. Thank you!