I have given it some thought and don't think I'll buy the house. I can keep renting here for $400/month until my roommates move out or until I need to relocate.
I've been given an update on the salary. $45k/yr GS7 for the first 6months, $55k/yr GS9 for the next year, $65k/yr GS11 the year after that, and then GS12 $75k-$80k 2.5 years after I start. He said 95% of the civilian engineers there are on a GS12 salary, so I guess that's as high as it'll go.
Assuming I wait 9 months or so to buy this car, I'll be making $80k by the time I'm ending the loan payments.
Fwiw, not familiar with the public sector pay scales but expecting a 80% pay increase and reaching the max salary cap in 2.5 years after starting the job seems a bit suspect.
As others have stated build up a rainy day fund first before jumping on the purchase of your NSX, cars are not an investment at all they are assets that will depreciate over time and you also have to keep in mind that once the mod bug begins you can easily spend a lot of money on mods.