The entity that transfers ownership interests in, or shares representing, units to eligible families, or another entity specified in the approved application, may use 50 percent of the proceeds, if any, from the initial sale for costs of the homeownership program, including improvements to the project, operating and replacement reserves for the project, additional homeownership opportunities in the project, and other project-related activities approved by the Secretary. The remaining 50 percent of such proceeds shall be returned to the Secretary for use under section
4110 of this title, subject to availability under appropriations Acts. Such entity shall keep, and make available to the Secretary, all records necessary to calculate accurately payments due the Secretary under this paragraph.