I just did it. It's super easy. I found out about it from the NSXprime board.
It's called Pentagon Federal Credit Union at penfed.org
1) Call and donate $20, they then open a savings for you with $5. They do it via credit card so have it ready when you call.
2) They then give you a member number and you apply for the autoloan on their website. If you have good credit, they should approve you right away and can overnight you the blank check for a small fee.
The limits are that they will only lend you up to the NADA value so check the NADA site to make sure that the car you want isn't over. If it is, then you just need to come up with the difference in cash or some other method.
This isn't BS. I'm in no way affiliated or gain from this.
I do hope that this helps stabilize sellers on here who think that the answer to selling is lowering their price.
