From big house to smaller flat: my Bangalore property puzzle

Honestly, I thought selling our big house and buying a smaller one would be simpler. Kids have moved out, so we're looking for a manageable 2BHK near Residency Road ya Cunningham Road. Prestige Group ke projects dekhe hain. Builder se negotiation kitna possible hai? Kya spot discount milta hai ya bas bolte hain no negotiation? Aur resale market mein zyada bargaining scope hai kya? New projects mein hidden charges kitne add ho jaate hain possession pe?