Apc site is under maintenance. I don't think anyone could mention duration for different loads since the backup time depends on battery AH. Max AH this inverter supports is 180 I think.
Yes but don't go by Bangalore prices. Mumbai prices are 3-5k higher. Also you will get exide IT500 battery instead of the apc battery mentioned and no trolley. Trolley was a plastic one which costs 1500 or so. Mumbai prices would be around 23k for the unit and battery. Don't expect them to do any wiring since they will only deliver the unit. All the home wiring would have to be done by your friend too. Will pm you the number.