I'm unsure why you would want to serve up what could be 30 seconds of free WiFi.
In this case, your best and cheapest plan is to not do this. Focus on your product instead.
Hey everyone, I planned to start a food truck in few months time. Currently, I am in the process of writing a business plan. I would like to provide wi-fi at the food truck. In that process, I need to figure out what equipment I need and how much they would cost me.
I would like to provide 30mb free data a day (not more than that) to a wi-fi device. I am thinking to take an unlimited usb modem, as I won't have a landline connection for a traditional connection. Remember, I won't have a desktop or laptop in the truck all the time.
I might be thinking the whole idea in a wrong way but I'm ready to mend my ways. Please advice me best possible and cheaper ways to provide wi-fi and equipment needed for that method.
Many Thanks in advance

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