I suggest anyone you hire can have the soul of a old fashion engineer and be
 urged to keep detailed records.  Everything from model numbers on the
 lawnmower to what brand of cleaner you use.  I once started at a small museum
 where the former director did not keep on such records and a storm knocked out
 the program for the complex electronic controls for the AC.  The nearest tech.
 for that system was 300 miles away!