2. How much stamp duty is charged on Agreement of Sale or Sale Deed?

The stamp duty in Pune city and Pune rural for sale of property is charged @ 7% and 6% respectively on agreement price or government price, whichever is higher. If the government price is higher, then depreciation may be availed to reduce stamp duty.
The registration fees @ 1% (max. Rs.30,000/-) is also charged. However, If the stamp duty @ 7% or 6% is already paid on Agreement of Sale, then the stamp duty on its subsequent Sale Deed document is levied @ Rs.500/- and registration fees of Rs.1000/-. only. (Currently, Stamp duty discount for women for buying residential property is reduced to 1% respectively till December, 2020)

3. Is Agreement of Sale or Sale Deed mandatory to be registered in the government registration office, i.e. Sub Registrar Office?

Yes, it is compulsory to register the Agreement of Sale and/or Sale Deed in the registration office, i.e. Sub Registrar Office as per the Indian Registration Act, 1908.