Or have, or at least have once had, a lucrative side business (military personnel can do this, legally.)
Or have inherited money.
Or have a spouse with a greater income or inheritance.
Or restore cars, such that the market value of their vehicles vastly exceeds the purchase price.
Or purchase cars that have significantly appreciated in value for other reasons (lots of high-end luxury cars that are limited run not only are pricey but limit sales to selected buyers, and the market value of the cars is almost immediately much higher than the purchase price and appreciates rapidly.)
Or a combination of the above.
Of course, it's also possible the general saved up, or made lucky investments, or married into money, or there was an exaggeration or misunderstanding.