; and (2) use the assistance for a down payment on a property to be used by the eligible household as a primary residence for a period of not less than 10 years. (d) No restriction on housing An eligible household may use assistance received from a grant provided under this section for a down payment on any type of dwelling that shall be used as a primary residence, including a manufactured housing unit, residential property under 400 square feet, a condominium, or a cooperative. (e) Unrestricted co-Borrowers pilot There shall be reserved 2 percent of the funds made available under this section for grantees to carry out a pilot down payment assistance program serving more than 2 co-borrowers receiving assistance from a grant provided under this section. (f) Supplement for shared equity home purchases A grantee shall establish a 25 percent supplemental bonus down payment for eligible households that are seeking to purchase an existing shared equity home or cooperative or bring a property into a shared equity homeownership program or cooperative with funds made available under this section. (g) Limitation The aggregate amount treated as acquisition indebtedness for purposes of this section for any period shall not exceed the limitation governing the maximum original principal obligation for a mortgage secured by a single-family residence, as determined and adjusted annually under section 302(b)(2) of the Federal National Mortgage Association Charter Act ( 12 U.S.C. 1717(b)(2) ) and section 305(a)(2) of the Federal Home Loan Mortgage Corporation Act ( 12 U.S.C. 1454(a)(2) ). (h) Authorization of appropriations (1) In general There is authorized to be appropriated to carry out this section $1,000,000,000 for each of fiscal years 2021 through 2030. (2) Set aside for Fund An amount equal to 20 percent of the funds appropriated under paragraph (1) in a fiscal year shall be set aside and transferred to the Restorative Housing Justice Fund established under section 113(h). (3) Set aside for Indian tribes Of the amount