(7) costs shall only be recoverable by a landlord pursuant to this subparagraph for an individual apartment improvement if, immediately subsequent to undertaking the individual apartment improvement, the landlord submits to the division of housing and community renewal any evidence that the division of housing and community renewal deems necessary and requests pursuant to regulation, operational bulletin or other guidance, evidence of the completed work. Such evidence shall include, but shall not be limited to, photographs of the completed work, itemized receipts for all parts, materials, appliances, and labor costs, and proof of payment. Provided further, the division of housing and community renewal shall require the payment of a fee that equals one percent of the amount claimed for the individual apartment improvement at the time of such filing;
(8) for costs recoverable pursuant to item (ii) of clause two of this subparagraph, the fifty thousand dollars may be expended, in the aggregate, on any number of separate individual apartment improvements in a fifteen-year period, but in no event shall costs above fifty thousand dollars be recoverable in a fifteen-year period pursuant to this subparagraph;