24 C.F.R. § 811.103 – General.

(a) In order for obligations to be tax-exempt under this subpart the obligations must be issued by a PHA in connection with a low-income housing project approved by HUD under the Act and the applicable Section 8 regulations.
1. (1) Except as needed for a resident manager or similar requirement, all dwelling units in a low-income housing project that is to be financed with obligations issued pursuant to this subpart must be Section 8 contract units.
2. (2) A low-income housing project that is to be financed with obligations issued pursuant to this subpart may include necessary appurtenances. Such appurtenances may include commercial space not to exceed 10% of the total net rentable area.
(b) Where the parent entity PHA is not the owner of the project, the parent entity PHA or other PHA approvable under § 811.104 must agree to administer the contract pursuant to an ACC with HUD, and such a PHA must agree that in the event there is a default under the contract it will pursue all available remedies to achieve correction of the default, including operation and possession of the project, if called upon by HUD to do so. If the field office finds that the PHA does not have the capacity to perform these functions, the Assistant Secretary may approve alternative contractual arrangements for performing these functions.