Kingvsvill eis near Corpus, so I am sure its a legite Naval address - is it a legite sale - who knows?
Thats why I say offer to use an escrow agent (or your choice) that will hold the funds and title, you will see if its legite real quick.
I will be driving past Kingsville on Monday on my way to Brownsville, so tell him somebody is coming to view the car.
If it is a scam I migh tjust bring the DPS with me and we can get someone to be arrested