There are lot of scams going on in sites like olx and quikr. Atleast olx has some genuine ads, quikr is just spam site operating as genuine site.
Person sets up an car ad for very low price. people call him. he says car is available and also tells him that he has two more offers waiting for him and advises the buyer to deposit small amount of money (1k~2K) to book the car. After money is deposited, the seller is no where to be found. I though people are too smart to fall into these traps. Guess I was wrong.
Olx has genuine sellers though for most part.