Sohna 2BHK hunt: Total cost confusion

Okay I'll be honest — I'm really struggling to get a clear picture on Sohna property costs. I'm based in Dubai and looking at investment options, maybe a 2BHK in Sector 70A, possibly MRG World. What's the real all-in cost for something around ₹90L? Beyond the base price, how much extra should I budget for stamp duty, registration, PLC, etc.? And honestly, how much negotiation room is there with builders these days? Can I realistically knock off 5-7% or is it more like 1-2%? Really worried about hidden charges when I can't do site inspections myself.