I am running an interior company under Indian accounting standard A11 construction contract and I am registered with VAT and CST in Tamilnadu now I got an order to execute an interior Project in Delhi but the client is in Tamilnadu region they were issuing Purchase Order to me in tamil nadu region but the project has to be execute in Delhi what are the taxable formalities to be done. Some experts please help me to do the documentation and laws to execute the same.