would base support that the project is an eligible project (as defined in this section), the owner cannot make the election of preferences for elderly families as provided by this section based upon primary sources alone. In any case where primary sources do not provide clear evidence of original design of the project for occupancy primarily by elderly families, including those cases where primary sources conflict, secondary sources may be used to establish the use for which the project was originally designed.
(c) Reservation of units in elderly projects for non-elderly disabled families. The owner of an elderly project is required to reserve, at a minimum, the number of units specified in paragraph (c)(1) of this section for occupancy by non-elderly disabled families.
(1) Minimum number of units to be reserved for non-elderly disabled families. The number of units in an elderly project required to be reserved for occupancy by non-elderly disabled families, shall be, at a minimum, the lesser of:
(i) The number of units equivalent to the higher of—
(A) The percentage of units assisted under this part in the elderly project that were occupied by non-elderly disabled families on October 28, 1992; and
(B) The percentage of units assisted under this part in the elderly project that were occupied by non-elderly disabled families upon January 1, 1992; or
(ii) 10 percent of the number of units assisted under this part in the eligible project.
(2) Option to reserve greater number of units for non-elderly disabled families. The owner, at the owner's option, and at any time, may reserve a greater number of units for non-elderly disabled families than that provided for in paragraph (c)(1) of this section. The option to provide a greater number of units to non-elderly disabled