The cost of the land shall be determined in accordance with the guidelines determined by the State Government for the purpose of payment of stamp duty in respect of registration of transfer of such land:

Provided that after payment of the tax of the value of the goods determined as per this rule, it shall be open to the dealer to prove before the prescribed authority that actual cost of land is higher than the value determined by the State Government authority for the purpose of payment of stamp duty for registration of land and the actual cost of land, being proved to be higher, the higher cost of land will be deductible and the excess tax paid, if any, shall be refunded/adjusted.