Can We Convert Hill Top Plot (2500-3000 Sqft) In Pune Wadachi Wadi Area To NA

I need your expert advice to suffice my need of purchasing plot and building my own house. There is currently a scheme in Wadachi wadi area Pune (Undri ) Where plots are sold on Hill top which is currently formed as gated society and each plot is provided with Individual Electricity Meter and Water connection. On enquiring with owners they confirmed that it I Agriculture plot and under Gram panchayat. To which he said couple of them have already constructed house with NOC received from Gram panchayat. I have couple of questions : 1. Is it okay to construct house with Permission from Gram panchayat . What will happen once the Plot will be under Municipality. 2. Can we convert Such Plots to NA . Also it is on Hill top currently . If yes than what will be rough estimate for the conversion of Plot to NA ( Plot Area is 2500-3000 SQFT) Please guide me with these issues so that I can take the best decision of purchasing the land.