If you haven't read of our experiences with electrical fire you'll find it in 'Montana Technical Help, Problems & Problem Solving'.
If not for the $30 cutoff switch I installed we might have lost everything. Because I had one I was able to cut the batteries off and put the fire out before more damage was done. The actual damage from the fire was less than $3000, it was the fall off the tow truck that did the other $17,000.
If you don't have one, get one.
If you've got one make sure it TOTALLY removes the batteries from the circuit. It's recommended that the switch be on the ground side of the battery circuit as close to the batteries as feasible.
We put a smoke detector in the storage cabinet as well. Close to the laundry door so we're more likely to hear it.
Keystone/Montana? Shouldn't you be doing this?