Hi Mike,
You can contact a national maintenance company such as DWM or Bonham. Most retailers seem to only want to write one check not 3000 so they use these companies who in turn sub out locals. These companies also provide other services to these retailers too. You won't get the price you charge but there are a few decent ones out there. This could keep you busy in the slow times and give a chance for your vehicles and personnel to be seen by the public.
Then make a target list from surrounding businesses as you now are known to be working for a well know retailer. You are seen, have credibility and a list of potential prospects. Then use old fashioned leg work.
I was able to target 10 businesses and gererate 7 estimates and or sales. Not bad considering 2% response on direct mail is considered good.
Bob