I have messured cheap 12V lesha drillmotors over 60 amps in stall @12V.
But if they have anything meaningfull over 10A, I would be very surprised. Over 15A you get nice heaters, but as drivepowersource it leaves something to be desired.

So, a cheap 12V batterydrill. My gut telling me, nominal 12V 5A (doesn't overheat), for our purpose 12V 10A (gets hot after 1 minute normal robot work), and brushburning in a fight 12V 25A.