I have been using Crompton Greaves Inverter for the last 2 years for my big 2 storey house. Its capacity is 1000VA.
Approximate cost when I purchased was Rs. 20, 000/-. So far it has been performing splendidly. When there is no power supply, I run my mixie, washing machine, fridge, grinder and even microwave for urgent use.(except ac). So for all these years I have never felt the difficulty of power failures. After 3 years, I just had to change the 2 exide batteries.
Other than that the product is working smoothly.In areas like us, where there is constant power failures, this product is a blessing.In both the floors, around 3 to 4 lights and 2 fans works along with TV also. All in all this is a very good product.