Buying a 3BHK in Kothrud: What hidden costs did you face?

Kothrud mein ek 3BHK dekh raha hu, Grand Unity Developers LLP ka project. I work in real estate, so I know builders ka marketing spin, but buying for myself is a different game altogether. Ek 2.5BHK ka quote mila ₹1.3 Cr ke aas paas, all-inclusive bol rahe hain. But I'm skeptical. Kya Pune mein spot discounts abhi bhi milte hain? Builders usually 'no negotiation' bolte hain but I'm looking for off-the-record advice. Secondary market mein better deal mil sakti hai kya for a similar property? I'm trying to maximise my total cost of acquisition. Kya hidden charges, like amenity charges ya society formation costs, baad mein surprise karte hain? Ya maintenance ka initial lump sum? Has anyone faced unexpected costs at possession time, especially in Kothrud?