British music mogul Simon Cowell may have hundreds of millions of dollars to his name today, thanks to the runaway success of his TV talent franchises Pop Idol and America's Got Talent.

But the 63-year-old wasn't always a savvy businessman. In fact, early on in his career, he almost went bankrupt.

In his late 20s, Cowell had some success working in the music industry as an artists and repertoire (A&R) consultant and signing novelty acts like the Power Rangers and puppets Zig and Zag.

It's then, Cowell said, that he got carried away.

"What I didn't learn about was credit cards," he said recently at Advertising Week Europe, recalling lessons from this career path.

"Once I started to make a little bit of money, then I just did everything a young A&R guy would do. [I] bought a Porsche, bought a house I couldn't afford," he said.

Before long, he'd spent all his money — and then some — and had to move home with his mom and dad.

"By the time I was 28, I was broke. I had to go back and live with my parents. I was nearly bankrupt, actually," he said.

In fact, it wasn't until about a decade later, in his mid-30s, that Cowell said he started to do "really well."

It was around then that he signed British boybands Westlife and Five, which went on to see massive success.

Soon afterward, he became a judge on the first series of Pop Idol, a TV singing competition he created with fellow music manager, Simon Fuller, which went on to spawn various TV talent shows including The X Factor and the Got Talent franchises.

Today, the entrepreneur is worth an estimated £390 million ($483 million), according to the latest edition of the Sunday Times Rich List released Friday.

Still, Cowell said that his early money mistake taught him an important lesson: "It taught me was I was rushing; I wanted everything to happen overnight."

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