Konkan Coast To Pune....heavily budgeted

Peanut Arms

Hello all you,
I am set to be traveling out of Mumbai in the first week of December with two companions. We want to spend a bit of time on the beach before heading into Pune where we will be attempting to do some volunteer work.
I wanted to know about accomodation and transportation along that coast.
First off, is it more time-efficient to take the train from Mumbai to Pen and then public transport into Alibag, or a direct boat from the Gateway in Mumbai?
What can we expect to pay in any of the lesser known beaches if we are aiming for the lowest possible price and quality level? MTDC? (I'm thinking of Murud and Malvan specifically). How about the bigger names (Ganipatipule, Alibag, etc.)?
How about finding accomodation with the locals? Difficult to arrange, or readily touted?
That said, I have a good deal of experience with tropical beach camping, is that tolerated in these locations? What if we find a more or less deserted beach in walking distance of a more populated on? Do seaside restaraunts or residences ever "rent" the beach space in front of them to travelers? This was a dependable method of traveling and assuring a place to stay for the night in Mexico. It seems difficult to track down camping regulations for India so i'm assuming it's not common...still...will it work?
Finally, how would we best make it to Pune from, say, Ganipatipule...again with budget taking precedence?

I realize that's a lot but any bit of advice would be much appreciated.