Service tax & vat

Dear Sir,

I have purchase my Flat in May 2010 in under construction , but at that possession time builder has oraly said you have to paid service tax and VAT otherwise we are not give you the possession so after that I have paid him the Vat & Service Tax amount  and I demand for receipt the same.

whenever I demand for receipt , he always ignore so please suggest me can I ask him to give the CA Certified VAT & Service Tax Working.