If The Taxi Driver Don't Turn On The Meter, Asking Him to Turn On Immediately

general speaking, if the cab driver don't use the meter, you would be charged more money. 

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and please wait for and take the receipt with you when arriving at the destination for in case some wrong with it. 

the licensed cab should stick the basic info on the front desk in the car, here is a sample:

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you may take the the info card a photo for incase

it would be better if you could get the around taxi fee online for reference in advance.