He’s not some brilliant financier, he just invested in real estate instead of buying dumb shit. Arkansas is literally one of the cheapest places in the US to live and own a home. 10-20k down payment on a rental property back when the interest rates were low and you’d be making money off the rent from jump street. Probably bought him another property after every fight or so. Plus he can do the maintenance and whatever renovations would have been needed.
Being able to build a house can also save you lots of money. No clue how good he is at it; I’ve seen some shitty builds.
He’s still a fucking moron, but he’s thrifty and frugal, which usually comes from growing up dirt poor.