Need advice on pump selection, types & factors in Maddur, Karnataka

I'm pursuing an horticulture project at Maddur. We had recently dug a 6" borewell and struck water at 100 ft. The total depth of the  bore is 400 ft. Can you please suggest what is the ideal HP rating of the submersible pump to be used.
The casing has been done for around 50 ft. Also what is the typical cost for such pump and what are the factors we should consider for selecting the pump.