Tax on selling under construction residential property

Dear All,

I have purchased an under construction flat in May, 2010 and would like to sell it in 2015 before possession.

I have paid this purchase value as on demand with construction linked plan and now will be paying “Ownership Transfer Fees to Builder to transfer unit to new buyer, Broker Charges” and also I have paid “Interest Amount” on home loan for this unit so far.

Would like to check how tax will be calculated.

I read online that it will be Capital Gain Tax considering CII Index as 711 in 2010 and 1024 in 2015 with formula to get current value = (CII Index in 2015/CII index in 2010) x purchase value in 2010)

And then see if calculated current value of flat is higher or lower to sale price of flat to compute Capital Gain Tax or loss.

Would like to check if I can deduct “Ownership Transfer Fees to Builder to transfer unit to new buyer, Broker Charges, and Home Loan Interest since 2010” from current value arriving after CII Index Calculation to compute Capital Gain tax or loss.

Thank you in advance for extended help.

Alok