of guidelines increases or, if no such regulated rent existed or is known, the commissioner shall impute a rent consistent with other rents in the building. The amount of hardship increase shall be such as may be required to maintain the annual gross rent income as provided by this paragraph. The division shall not grant a hardship application under this paragraph or paragraph six of this subdivision for a period of three years subsequent to granting a hardship application under the provisions of this paragraph. The collection of any increase in the rent for any housing accommodation pursuant to this paragraph shall not exceed six percent in any year from the effective date of the order granting the increase over the rent set forth in the schedule of gross rents, with collectability of any dollar excess above said sum to be spread forward in similar increments and added to the rent as established or set in future years. No application shall be approved unless the owner's equity in such building exceeds five percent of: (i) the arms length purchase price of the property; (ii) the cost of any capital improvements for which the owner has not collected a surcharge; (iii) any repayment of principal of any mortgage or loan used to finance the purchase of the property or any capital improvements for which the owner has not collected a surcharge and (iv) any increase in the equalized assessed value of the property which occurred subsequent to the first valuation of the property after purchase by the owner. For the purposes of this paragraph, owner's equity shall mean the sum of (i) the purchase price of the property less the principal of any mortgage or loan used to finance the purchase of the property, (ii) the cost of any capital improvement for which the owner has not