ritz or i10.... both are small good and easy to maneuver in the city ...... i10 offers nice diesel engine with refinement and steering is also light which is good for city..... ritz would give you resale value.... choice is yours
Go for the Swift, its spares are easily available and the car is cheap and easy to maintain.
You mean the Grand i10? It's a very good city car but finding one won't be easy as majority sales of the Grand i10 are petrol.
If its used search a i20 instead they have good mileage.