Answer for We are serving clients out of india & therefore do not charge service tax & do not pay to govt.is service tax paid in putting our efforts ie.monthly rent,purchase of computers etc refundable?

Yes, you can apply for refund. You will have to take registration no, file regular tax return and refund application. 
Note – It is suggested if the amount of refund is significant to you as while giving refund officer checks various documents eg rent agreement, purchase bills etc.
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