; (ii) compensate those experts and consultants for each day (including travel time) at rates not in excess of the rate of pay for level IV of the Executive Schedule under section 5315 of that title; and (iii) pay to the experts and consultants serving away from the homes or regular places of business of the experts and consultants travel expenses and per diem in lieu of subsistence at rates authorized by sections 5702 and 5703 of that title for persons in Government service employed intermittently. (B) Limitations The Chairman shall— (i) to the maximum extent practicable, limit the use of experts and consultants pursuant to subparagraph (A); and (ii) ensure that the employment contract of each expert and consultant employed pursuant to subparagraph (A) is subject to renewal not less frequently than annually. (c) Additional compensation authority (1) For new employees The Chairman may pay a person recruited and directly appointed under subsection (a) a 1-time hiring bonus in an amount not to exceed $25,000. (2) For existing employees (A) In general Subject to subparagraph (B), an employee or other personnel who the Chairman determines exhibited exceptional performance in a fiscal year may be paid a performance bonus in an amount not to exceed the least of— (i) $25,000