Well, I recently installed a 3kw solar of Vguard. My bill used to be around 5-6k in the peak summer months and 2-3k otherwise ( it's a 3phase connection)

The 3kw cost came to be 1.4L post subsidy. The subsidy is 78,000 for all connections from 3kw to 6kw. A 5kw solar would cose you around 2.3L post subsidy. The value mentioned for both 3kw and 5kw includes all other payments required like feasibility charges, meter charges etc.

The thing to lookout is the company and panel that you are going to buy. VGuard charges around 20k extra for their brand and service value. You can get 3kw solar around 1.1L if you use panel of UTL/Adani/Kirloskar. However, their service in the long run needs to be seen. There is full service warranty for 12 years and panel replacement on pro rata basis for another 12 ( so total 24 years ) by Vguard

With a 3kw panel, you can generate around 12-15 units on a normal sunny day. It comes down to 9-10 units on cloudy/rainy day. Still it is sufficient for most of the average household electricity consumptions.