My 3BHK hunt in Mohali and crazy premiums

Spent the whole Sunday checking out 3BHKs in Mohali, especially around Sectors 69-71. My wife really liked a Godrej project, but their PLC and floor-rise premium seem crazy. For a 4th floor unit, they're adding like ₹7L extra. Is that normal? Kids' school admission is coming up, so we need something safe soon. I'm wondering if these charges are negotiable at all. Can you actually knock off a significant amount on these premiums in Chandigarh, or is it mostly fixed? What are your experiences?