refund of credit

A person is estimating to have credit of Rs. 750000. of Vat.Out of this around Rs. 650000 credit is due to inverted tax structure (Input vat rate 15% output rate is only 5%).whether he can take refund of the same?

what are the provisions for refund if it can be taken?

he is also proposed to levy gst on service by way of renting of immovable property.