Rooster McConaughey and Butch Gilliam carved their fortunes from nothing.
Today, the self-made multimillionaires are passing on their wisdom by investing in ambitious entrepreneurs on their show, "West Texas Investor's Club." It's similar to Shark Tank, with some beers mixed in.
If you ask them about their most valuable possession, however, they won't name something that came with a hefty price tag ... or a price tag at all.
"When you look back, and one day you're going to be looking back, it shouldn't be the amount of money that you made that should be your most valuable possession," Gilliam tells Business Insider. "It should be those relationships with your friends, your customers, and your family. That's the gold of it all."
"That's the riches right there," McConaughey chimes in. "And, who wants to do it by themselves anyways?"
Besides being in good company, developing strong relationships could consequently boost your net worth. As author Thomas C. Corley found in his five-year study of the rich, "relationships are critical to financial success."
Rich people take the time to build relationships with other success-minded people, and they realize that the little things — such as a five-minute phone call — add up. According to Corley's research, 80% of wealthy people make birthday calls, hello calls, and life event calls, compared to 11%, 26%, and 3% of poor people, respectively.
Will calling your friends make you rich? Certainly not. But it can't hurt. Plus, as McConaughey says, "What good is anything if you're not surrounded by good people?"