You must be referring to an auto rickshaw commonly called autos all over India. They are very plentiful in the city of Varanasi and probably the best means of transportation in this very crowded and chaotic city. How the driver would get his services listed on Trip Advisor, I would not know. Usually, Trip Advisor only lists hotels and eating establishments and local sights etc.,
You can find lots of Tuk Tuk driver. Fix up price before and pay only when you are back.
There are plenty of drivers around. Check the prices agree the deal and ensure they wait for you on return journey.
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