Validating entries while adding driver profiles

Validate entries while adding driver profiles

In the admin section under manage drivers:-
Under add drivers the following can be done:
Restricting input of the type of car to the predefined car models and nothing else.
Validating phone number entered (should be 10 digits, first digit should be between 6 and 9).
Check for repetition of phone numbers. Repeats shouldn't be accepted.

Optional:
Add a maximum and minimum limit for the cost per km entry. The maximum and minimum limits must be different for each car model.

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