Specifications include, but are not limited to: Purchase of pre-owned, remanufactured, and rebuilt heavy-duty transit buses that will provide the best value and selection to purchasers that maximizes passenger appeal in appearance, comfort, and safety, combined with excellence in reliability, operating characteristics, and economy of operation. Heavy-duty buses purchased under this RFP will be 30’, 35’, 40’, 45’ and 60’ BRT articulated; and diesel power or electric propulsion system; or any combination thereof. Buses shall have a minimum expected life of six (6) years or 250,000 miles, whichever comes first, and are intended for a wide possible spectrum of passengers, including children, adults, the elderly, and people with disabilities. The buses shall be Altoona tested and meet any other bus testing requirements under MAP-21.