; and (ii) the completion of any quality assurance assessment required under subparagraph (B). (B) Quality assurance assessments The Secretary shall establish a schedule of required quality assurance assessments. In the first year of the Program, the first 10 homes retrofit by each contractor and then 60 percent of all future homes shall be required to have a quality assurance assessment. The Secretary shall establish a cost effective schedule of required quality assurance assessments for subsequent years based on performance under the Program. (C) Bonus incentive Recipients of grants under section 32109 and rebate aggregators are encouraged to present a proposal to the Secretary for an incentive bonus for contractors who have delivered services to consumers and who have achieved a 70 percent or greater realization rate for predicted gross energy cost savings achieved by their portfolio of participating customers. Bonus incentives under such a proposal may be up to 20 percent of the rebate paid to the homeowner. (3) Limitation In no event shall the amount of rebates under this subsection exceed— (A) $10,000 with respect to any individual; or (B) 50 percent of the qualified home energy efficiency expenditures paid or incurred by the homeowner under subsection (c). (c) Qualified home energy efficiency expenditures For purposes of this section, the term qualified home energy efficiency expenditures — (1) means any amount paid or incurred by a homeowner for a qualified home energy efficiency retrofit, including the cost of diagnostic procedures, labor, reporting, and modeling; and (2) does not include— (A) improvements to swimming pools or hot tubs; or (B) any amount paid or incurred to purchase or install a biomass, wood, or wood pellet furnace, boiler, or stove, unless the system— (i) is designed to meet at least 70 percent of the heating demands of the home; (ii) in the case of woodstoves, is certified by the Environmental Protection Agency