Possession delays and hidden costs are killing me

Possession for our Whiteland Urban Resort flat was promised for March, but we only got it last month, almost two months late. The delay was a real pain, had to extend our rental agreement, which wasn't cheap. Honestly, the brochure showed one thing, but the actual carpet area feels smaller than what was marketed, especially in the living room. Plus, the maintenance charges are way steeper than what they indicated during booking; it's adding a significant chunk to our monthly outgoings. We paid around 7 crores for a 3BHK, expecting a certain standard. Did anyone else who bought in Whiteland Mohali face such issues with project delivery or hidden costs? What did you do about it?