School/sports team fundraisers work well - Cover cost, make a little money, and get your name out to the local crowd in just a few hours.
One method that has always worked is cold calling larger businesses - 100 + employees. We hit an office park with flyers, and Pulled Pork - We go into every business and ask who books their employee appreciation lunches or customer events, and invite that person out to our rig for a Pulled Pork slider. Minimal cost for a big impression.
We also use lead generation sites for Catering like decidio.com, localcatering.com, etc. Best of luck!
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