Pre-launch pricing ka asli game, koi batao

Did a site visit to an SBP Group project in Zirakpur on Saturday. Pre-launch offer ke naam pe they're showing one price, but jab paper-work pe aaye, toh PLC, floor rise, maintenance advance sab add kar diya. Builder ka yeh game samajh nahi aa raha. I work in real estate but buying for myself feels so different. Kya sabke saath aisa hota hai? How to avoid these hidden costs yaar?