This is not a Technical query.Simple thing about buying a transformer is Place a purchase order with detailed specifications clearly spelling out your requirements and get an order acce[ptance from the supplier.If the supplier is in the same state where you are located you have to pay local tax and C form is not applicalbe.If he is in a other state you can avail concessional sales tax by giving form C if u are eligible.Why don't you discuss with your finance guys who can guide you better on thisaspect.
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