Corpses-Я-Us: Or, Buying Dead Bodies For Fun And Profit

[Coidzor]

Spells are more expensive then wagons.

But wagons are more readily liquid, generally, and are a stand-in for just about anything. A single repair spell, to my recollection, has a negligible material component cost covered by a spell component pouch.

Even just with masterwork weapons, parting one out and then repairing each part into a whole weapon would be a profit. Otherwise, if spellslots are readily liquidable, if they ever have any downtime the casters start to take in a bunch of money per day just based on their spell slots.

[ShurikVch]

Spells "Repair ... Damage" don't have material components.
But DMG have prices for NPC spellcasting.

10 gp per spell level × her caster level

I don't see why PC spellcaster can't grant such services.

Let's say you rip the piece equal of 1 hp.
And light vagon have 60 hp. (Ultimate Combat Vehicles)
You can use, say, Repair Light Damage spell.
Even if you are 1st lvl spellcaster and get ideal rolls every time, you are going to spend at least 70 gp of spellslots to get something with selling price of 35 gp.

And the more high-level your PC, the more expensive become your spells. Single cast of Repair Critical Damage will be cost as 8 wagons.