Start-Up HELP!

Hey guys,
So a little background on me, I just graduated from a Non-target school. Back in my home country now (India) after graduation due to lack of opportunities. Currently working in Institutional Equity research (Sell-Side) at a boutique firm. I have this idea for a start-up that I could use some advice on.

Some facts about the idea:
- It solves a major issue in the daily life of people
- The industry, currently, is highly unorganized with no professional companies currently invested in it

The problems I am facing: (NO MONETARY PROBLEMS- Expect to be fully funded)
- Working out the logistics and the economics of the idea to make it sustainable in the future (Bottom line Profit-making within 3-5 years)
- The idea in its basic terms is scaleable (Can be applied to any city in the India) but after looking at the logistics and assumptions I have made, it doesn't make sense.

So I could really use some advice/recommendations on how to proceed with this. I have already done a market survey and that has reaffirmed that the idea is needed in the country, but the implementation of it I am struggling with.

Can anyone out there help me?
(PS: I know I was ague about what the idea is about but thats how much I could tell without giving it away)