I think I would scan the house quick and go for the fast cash first. large appliances and wires of everything, furnace, ac unit. Stack the truck with the bigger stuff first.
Then I would go for the copper. Starting from the water meter and bust the walls to the sinks and where every they go.
check the drawers of everything for any stashes, cabinets, heat registers, any boxes
gather all the silverware and pots and pans (usually stainless or aluminum) Hopefully some silver.
look in the garage for tools and other heavy metals, buckets of fasteners
If the wires look silver and not copper being an old home I would concentrate on those.
next anything with motors or brass .... fans, door hinges & knobs, bathroom fixtures. sinks
if the magnet doesn't stick to it, take that next.
last the little steel tins stuff, chair legs, knick knacks... remember to fill any steel file cabinet and the washer and dryer with the little stuff.
of course anything that is of interest I would take as well
I agree with mnplumberman, I would move quick, pack a lunch and take some energy drinks and toilet paper. If there was that much good stuff I would stay all nite and probably call off of work to sleep the next day.
also if the floors are wood and you have time, run through with the metal detector ... maybe some coins are hidden in the floor boards!
let us know how you do and good luck, hope we helped
Rumblebelly