Managing Expectations

Many of you have heard our vehicular story of 2014. My poor old truck was queued to be replaced. 1998, 196,000 miles, rusting down at the bottom of most of the panels. 
Then, I totaled my husband's car in January in some drifting snow, and he got bumped to the front of the line. 

The great part about this part of the story is that I had been looking at the new Camaro as my replacement vehicle, but had just come to the realization that it wouldn't work as the dogs hate the deep bucket seats in the back and I am the primary transporter of our furry little babies. 

My husband is 6'4" and does not fit into a lot of cars, and fits comfortably into even fewer. So, it was a bit of a win for me when he decided that was going to be HIS replacement vehicle.  
Of course, it's painful to consider going from a house with zero car payments to a house with 2 car payments. 
So now we are finally are near the point to replacing my truck, I don't quite have the down payment saved back up, but possibly the perfect car has appeared. 
I've been trying to manage my emotions and expectations, but my husband's excitement is winding me up like a kids top at Christmas. I feel like I'm going to be dead meat for the car dealer.
How many times do we let ourselves get overly excited with the anticipation of something?
How do you keep your emotions and your expectations in check? I'd love to hear your suggestions.