Type of Vehicle - some people are just fine with a Toyota, Skoda or an old taxi vehicle and some would prefer a more comfortable car. Vehicles differs in acquired price, comfort and maintenance fees
Used Tyres - this is the most common taxi maintenance savings that some taxi operators and drivers does. Having used tyres maybe still fine but are you really going to take a chance?
Maintenance - we all knew that if you bring the car to the dealer, most likely, you will pay for the higher price, it's fine to have the maintenance done by your local garage but some taxi drivers or operators do the maintenance themselves even the job should be done in a proper garage, machine against human when it comes to quality of work seems a good choice
In-experienced drivers or chauffeurs - an experienced driver will be able to save you time without compromising the safety of the journey. Training and experience are the two most important factors that will make your journey better as drivers with less experience may delay your journey
Taxi service quality - this is the most important factor as others who does cost cutting in manpower and maintenance may give you a negative taxi experience