Charges refund: cancellation or resale - which is best

Hi Experts, Actually I have bought a flat and got its registration done in Pune during June 2017 and builder promised to give possession by December 2017 and till date we have not got the possession and expecting it by June 2018. Looking at this delay I asked Builder to cancel the flat and was agreed by builder as well. But builder suggested me to wait till possession looking at the demand of flats so that flat can be sold at good price. Builder has no issues in cancelling the flat, he also mentioned that in case of cancelling the flat I will be getting stamp duty, registration charges, VAT, Service Tax refunded in case of cancellation with in the span of 2 years. 1. May I know if its true that all charges stamp duty, registration charges, VAT, Service Tax refunded if I cancel the flat before June 2019 (i.e., with in 2 years from date of registration) ?? 2. Will all the above charges will be refunded in case if I resale the flat after I get possession with out occupying the flat. Please suggest or let me know if any queries.