Exemption u/s 54f is allowed only on agrement value of flat or on entire cost?

Hello, I want to claim exemption u/s 54F by investing in one residential property, my agreement value is around 79lac, Will I get exemption only on agreement value or on an entire purchase cost of an under-construction of a flat which includes stamp duty and registration charges @ 5lac, GST payable on under construction on a flat @ 4lac and one-year advance maintenance charges @ 1lac rupees. + 79lac which is agreement value cost.

Please reply and thanks