This looks like an interesting business idea because it reduces lines by distributing points of sale all over the truck. I see high overhead and the need for a very good electricity source. The idea is interesting.
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I am not sure what kind of electric generator is needed to operate all of these machines, but my concern is that if it breaks, any frozen item will spoil. http://www.electricgeneratorsdirect.com/power/portable-generators.html.
My next thought is, how does one lift and drop the truck when it is time to stop and go? ( sorry about the bad construction of that last sentence) I went to yahoo and found some information about hydraulics.