THIRD: Don't exceed your maximum bid (determined above). Allow LOGIC to rule the day, rather than EMOTION.
You've already added your "personal passion premium" to the market value, to determine the number where you are, quite literally, happy to walk away.
So ... BE HAPPY.
If you lose, hold your head high in the knowledge that:
- you may have lost to a drunk bidder, who's gonna relist the car somewhere as soon as his wife finds out what he spent!
- you may have lost to the owner (or his proxy), who will also relist the car somewhere within a year or two.
PLEASE REMEMBER: If you are passionate about these machines, you're in it for the LONG HAUL. You're not a day trader

If you've done your homework, the chances are VERY HIGH that the car will find its way back to you within a couple years (yes, it's happened to me). Please be patient