1.6 is a better buy in rolla and value for money ,if you have to go for 1.8 , civic is a better buy compared to grande , as civic has a much better resale in 1.8 category.
Corolla doesn't lose its value, you can book you car now, get its delivery in Dec and register in 2021. You won't lose money even when you will sell.There is a reason behind this car being the most selling car in the world. It doesn't lose its value.
Considering the Rupee devaluation trend, you should book your slot for December Delivery. In my opinion it will retain its value as Rupee Dollar parity is speculated to increase.
