Expandable reamers are configured to operate in a first, retracted state in which a plurality of blades is in a retracted position when a sliding sleeve is in a first sleeve position and a seat is in a first seat position, to operate in a second, extended state in which the plurality of blades is movable to an extended position when the sliding sleeve is in at least a second sleeve position and the seat is in the first seat position, and to operate in a third, retracted state in which the plurality of blades is returned to the retracted position when the sliding sleeve is in the at least a second position and the seat is in a second seat position.