I'd say that a netbook with 3g internet would be a worthwhile investment, so you could check for new deals even while your out on the job. Then you'd always have your next destination, you could plan routes efficiently, etc.
I have a 7" samsung galaxy tab with built in 3g from verizon. I also have a dash mount so I use it as a gps as well as to pull up emails, addresses and listings on the fly. It also acts as a hot spot to give internet to my laptop when I'm traveling.
Couldn't you make some application which scrapes Craigslist every 5 minutes and detects newly posted items, maybe filter them on some criteria, and SMS them to your phone?
The CL app can do that for you. Say, you save a search for "refrigerator" in a certain area, in the "Free" category, the app would notify you (it puts a # on the top bar of your phone) letting you know there's a new listing for "refrigerator". Same thing for "roommate" or "carpenter" jobs, etc.
It's pretty cool, wish I've known this app when I was looking for a free carpet.
Interestingly enough, just last month, I bought on CL and sold a pair of girl's snowboard boots for $15 more in a matter of 4 days. Mostly because I really didn't want it.I was just practicing on my selling skills. I'm more inspired after reading this.
