My first home hunt: Hidden costs and negotiation in Greater Noida

Since January I've been shortlisting flats in Greater Noida, and honestly, the sticker shock is real. My budget is around 80L for a 2BHK. I recently saw a project by SDS Group in Sector 18, quoted around 78L for a 2BHK. But I'm so confused about the *actual* all-in cost. Builder sales team sirf base price batate hain. What about stamp duty, registration, PLC, parking, and all those interiors? Are there hidden charges that only appear during possession time? Like some utility connections or maintenance deposits? Also, negotiation kitna work karta hai Greater Noida mein? Can I realistically expect to knock off a few lakhs, ya fir builders don't budge much for end-users? Any advice on avoiding these surprise costs would be super helpful.