Others may disagree ... but if it's the first one, I typically go BIN/BO and wait for a reasonable offer. Otherwise, if you do auction I would say start it at around the final sale price of some of the other mid-tier relics.
LOOKING FOR GREG MADDUX:
~~~~~~ 2011 Topps Hope Diamond SSP #/60 ~~~~~~
~~~~~~ 1987 Donruss RC & Donruss "Rookies" - Raw & Graded ~~~~~~
~~~~~~ On-Card Autos in Braves Uniform ~~~~~~