It is evident that the demand and price of any product is commensurate to each other. A lower price with moderately good performance increases demand, and an increased demand helps in mass production which again makes the cycle complete as it helps in keeping the rate low.
In general every newly introduced model or newly redesigned cars undergo a season of high demand in the first few weeks or even months once they reach the showrooms and attracts media attention. The manufacturer would go busy in producing as many number of the car as possible within the least bit of time. But what happens is that the demand from the "first on the block" consumers generally outweighs the supply too far.
Currently the lowest price cars that have reached the top of popularity and usage are:
Tata Nano : 2.17 lakhs to 2.44 lakhs,
Maruti Suzuki Alto 800: 2.81 lakhs to 3.06 lakhs
Maruti Suzuki Omni: 2.57 lakhs to 3.05 lakhs
The range differs as per the city it is purchased in.