Rajkot investment: Agent quotes, but what about the fine print?

Got an update from my agent about a 3BHK near 150 Feet Ring Road, maybe Balaji Group ka project. Quoted around ₹85L. I'm based in Dubai, can't check things myself. My main worry is the final cost. Is stamp duty negotiable in Rajkot? Aur possession ke time pe kya hidden charges aate hain? Thinking about power of attorney for registration, but need to be sure about total cost of acquisition.