A normal used car can be sold and purchase by any individual or any local car dealer
but a pre-owned certified car can only be sold by its authorized company. Maruti and Mahindra are two main companies who deal in buy and sell of pre-owned certified cars. A normal used car dealer doesnt provide the services which have been offered by the authorized companies. The main difference between these two categories of car lies in two major differences. One is the facility of warranty that a pre-owned car dealer provide but no the local car dealer and second is the difference of cost.
A local car dealer never provides a warranty facility once his car has been sold out his liability towards the car is almost over. His main objective to sell his car is to fetch the maximum money from his customer. But in pre-owned certified cars you get the warranty and a few free services from the authorized service center of the company. They minimum offers one year of warranty it shows that their prime motive is not to fetch the lucrative benefits but to provide satisfied services to their clients. A normal car dealer at times do not have a service centers so in such cases either if he is willing to provide a free services to his client he cannot offer.
The second difference lies on their prices because in pre-owned cars you cannot get a discount or the chances of negotiating the prices are low. But if you are willing to buy a used car from a local car dealer or any individual the chances of negotiating prices are quite high. Whether you are in any part of the country for instance, the prices of used cars in Chennai must differs from the used cars in Hyderabad but in pre-owned car it is not so because excluding the taxes the prices of the certified cars is almost same across the nation.