Day & Night taxi Fares
by The Shoestring Traveller
(Reading, Pennsylvania, USA)
Bombay Taxiwallah - royalty free image by flinty
I know in Tunisia (and probably elsewhere), taxis have two setting on their meters - one cheap one for days and another, more expensive one for nights. So if you detect the driver surrepticiously throwing a switch on the meter, make sure he goes back to the "day" setting.
Also, make sure that the fare quoted includes luggage, or if not, how much extra for your luggage.