Tata Nano; Price Range: Rs 2.34 to 3.26 lakh; Mileage: 22 kmpl
Datsun Redi-Go; Price Range: Rs 2.41 to 3.75 lakh; Mileage: 23 kmpl

Maruti Suzuki Alto 800; Price Range: Rs 2.59 to 3.8 lakh; Mileage: 25-33 kmpl
Renault Kwid; Price Range: Rs 2.7 to 4.57 lakh; Mileage: 23-25 kmpl

Tata Tiago; Price Range: Rs 3.27 to 4.99 lakh; Mileage: 23-27 kmpl
Maruti Suzuki Alto K10; Price Range: Rs 3.38 to 4.2 lakh; Mileage: 24-32 kmpl
Datsun Go; Price Range: Rs 3.29 to 4.24 lakh; Mileage: 20 kmpl

Datsun GO Plus; Price Range: Rs 3.84 to 5.00 lakh; Mileage: 20 kmpl
Hyundai Eon; Price Range: Rs 3.3 to 4.56 lakh; Mileage: 18-21 kmpl
Maruti Suzuki Wagon R 1.0; Price Range: Rs 4.2 to 4.84 lakh, Mileage: 19-27 kmpl\ You get two kinds of Wagon R in India, the one in pic below and the regular design.
However, the best selling car in the country is a compact sedan by Maruti-Suzuki the D'Zire which sold 34,305 DZire cars in September 2017!
2017 Maruti-Suzuki DZire