My ₹3Cr Shanti Niketan search: the true cost puzzle.

Honestly, I'm still trying to grasp the actual total cost of property here. I'm eyeing a 3BHK in Shanti Niketan, perhaps a Vishal Developers project, around the ₹3Cr mark. The basic price is one thing, but then stamp duty, registration, PLC, parking, and fit-outs add up massively. What's a realistic percentage to factor for these 'extras' on top of the base price? And payment plans – is a construction-linked plan always better for capital preservation, or can a down payment deal offer better negotiation leverage? Trying to find value in this market.