Bannerghatta 2BHK buyers: What's your real all-in cost experience?

Fed up of renting, I'm finally looking for a 2BHK in Bangalore, possibly Bannerghatta. My budget is ₹85-95L all-in. Seeing Habulus Structures. Is negotiating 5-7% off realistic? Are pre-launch prices truly better, or do hidden costs like PLC, registration, and other charges just balance it out later? What's the real 'all-in' cost I should budget for? Any advice?