How do taxis work?

Could you tell me how you would say these 3 sentences?
1 The taxi starts charging from where it is if you call for one so by the time it gets to your house it'll have 10 pounds on the meter so you are better of hailing a cab.
2 We charge from the moment you get into the taxi.
3 The meter starts [running] the moment you get in.

Is the following question correct and mean anything?
How do taxis work?

Thanks in advance