He acquired a 4 unit, a 3 unit, 3 townhouses, and a farm. 

I'll start off by saying believe in the power of CL (craigslist) I don't let a day pass   without utilizing that site.my advice to you would be log on CL search area's within a 2hr distance from you go under real estate fsbo filter your search with we buy house's or I buy ugly house's and investor special,once you find these ads start making phone calls,reason being these investors know their local market and have their hands on the pulse of that farm area.After dissecting all the useful info from local rei,I generally go to google streetview and walk the neighborhoods to have a better understanding of there market.Trust me it works I just closed 3 wholesale deals in Birmingham,Al using those same techniques,I was fortunate enough to find a we buy house's sign on a street corner zoomed in on the sign called the number and almost 2 months later the deal was funded.I hope this post serves you willCheers!

Nothing I could do to fix the neighbor's house/farm, though.  

I have been building a DFW investor list so I can contact them to learn what they are looking for to determine my farming area. 

While you could do it yourself, I take it you're an investor and not a property manager. unless you're trying to buy your way into a job, farm it out.

If you know where your next duty station is at, then you can start getting in touch with local investors and get a headstart on farming the area.

Too bad they mostly only teach  how to farm listings when they 'train' new agents.  

I pay $45 per mo. for property radar and $28 per month for Rebo gateway by benuteach I found both as a referral from my title rep at first American title, our success is 95%.To speak more to what I'm doneing, we are developing a "FARM" I do the same type of drive for dollars type of thing only I want people to be living in the home.   

We made a commitment to putting 15 homes under contract in November and December and it has paid off big time for us.  3 deals closed 4 getting ready to start and 5 other contracts still going waiting for short sale approval.Well it's time to double down,  I'm starting today to work my farm.  

I agree but the big sharks move in first and it filters down to the little guy You have to have the expertise and vision to sniff out those neighborhoods that might change early An example was downtown Vegas 5 years ago The ceo of Zappos started buying on Fremont street  years ago and investors quickly moved in when they got wind of it Today is a desirable area with upscale tenants Your expertise is to sniff out these events early and take advantage It is not something t  laugh at but to capitalize on thru farming your area