His answer which became my #1 pricing rule: Whatever price you can back up, if someone questions it.

USS Grampus Submarine Boat Puget Sound US Navy Yard Washington 1910c postcard HipPostcard #18174910

The invoice date for an OLD Bidstart invoice ie Invoice #12738 from 06/22/2014; the original date is shown in the listing, but when asked to be printed it assumes a Sept. 2016 date 9/7/16 or 9/8/16