Just imagine going to 8-15 houses a day on service calls. Heh, I have my tool pouch/bag pretty organized, but there is still 5 screwdrives, pry bar, plier, putty knife, wire stripper, Klein diagnal cutter, wire crimper, snap ring plier, long nose, extra long - long nose, slip joint plier, avaition snips, sheet metal crimper, 2 Cresent wrenches, folding knifem fluke, cordless impact, bit holder with about 20 size bits, meter, plastic tray with extra screws, wire nuts, connectors, microswitches, 1 15/16" socket with 1/4" drive, rachet, flex driver extension, 3 larger drill bits, chisel, electric tape, 5-10 hose clamps, water test strips, 3/8" wrech, plus extra crap that accumulates. Quick glance and I can see if anything is missing. But, lost a $30 Klein cutter the other day, the cheaper ones suck and got a Dewalt brand and a cheaper one before I said screw it and got a new Klein again.
Workbench in garage is a disaster also. But most tools get put back in their home in one of the 3 rollouts under workbench.
Work van is another story, needed a part for a washer the other day and it was not in the proper tool box. So I start putting stuff away and low and behold 10-15 minutes later, one of the last parts that were out of place was the part needed. I usually stock 300+ parts. It is so nice when you know where everything is. There is times you spend tons of time cleaning stuff up looking for what you want, and you forget what you were doing to begin with.
One of the best things I got is a this:
Save a ton of time switching out bits and the swivel is awesome for hard to reach spaces.
This screwdriver is a handy one to have also: