Ariz. Rev. Stat. § 48-4542
A. The board, subject to this article, may:
1. Issue its negotiable bonds in such principal amount as, in the opinion of the board, is necessary to:
B. The board shall authorize the bonds by resolution. The resolution shall prescribe:
E. The board, out of any available monies, may purchase bonds, which may thereupon be canceled, at a price not exceeding the following: