How many cuts?
Where? Fab shop? Field? On top of a tower holding on the saw with one hand in 100 km/hr winds?
How accurate do you need to be? have you got the cut laid out already, or do you need repeated vertical/perpendicular cuts of a specific length? Will you use the cut-off piece, or the retained piece? How are you moving the original and the two remnants out of your saw? How long are the cut piece and the remnant? Will you need a crane, fork lift? Two people? Rollers?
Who is available to do the cutting? How good are they? How repeatable are they if given the tools? What is your budget, and what is your schedule? What tools are available in your tool crib? Your shop? Your pickup? The worker's tool boxes or welding kits? Are welders available to burn? Or can you burn at all? Is acetylene and oxygen available? What voltages or shop air will you need, do you have available? Fixed position or do you need to move the saw?
What size kerf is allowed? What type of cut is needed? (Do you need to grind and smooth the finish, leave as-is, grind and weld it, prep it for painting or powder coating? Sandblast?
"I'm hungry and need to eat dinner. How much will it cost me?" 8<)
No, we cannot (properly/thoroughly) answer your question with this little information.