Same frags, same two sheets, same gear and the same Level 2 bench as the fixed ballista. The calculator can't tell them apart, so the only real question is what you want it for, and it needs an answer before the craft.
Changing your mind later is expensive. The recycler hands back one of the two sheets of metal, half the frags and the gear only now and then, and sheet metal is always loot, the gear for most of a wipe. Build the fixed one, decide a week later to go raiding, and you have thrown away a sheet and probably a gear.
Watch out
The wheels only move behind a saddled horse. A double saddle cannot be crafted at all, only looted or traded for, so get one before raid night, not during it.
The two are separate blueprints at the same price. Learn both only if you really run both; a group that raids more than it defends learns this one.
Questions
Mounted Ballista ×10: how many resources?
Metal Fragments ×2,500, Gears ×10, Sheet Metal ×20.
Which workbench does Mounted Ballista need?
Workbench level 2.
How long does Mounted Ballista take to craft?
25 s for one, every step included.
How much scrap does researching Mounted Ballista take?
