These entrepreneurs are on Business No. 3 - at least

• Name: David Hauser, 31
• Current business: Co-founder, Grasshopper, Las Vegas
• Successful companies: 5

The first real business I had was doing website design when I was 14 or 15. By my senior year of high school, I'd started Return Pass, an email management service. That was my first real success, and I ended up selling it before I was done with college. It's still around and now has about 100 employees.

I've actually probably invested in 15 or 20 business ideas, though I've started and closed many more than that. Everything I'm doing today with Grasshopper, which is a phone system for entrepreneurs, has been influenced by what I've done in the past.

For example, in my first companies, I was really focused on making money for me. My goal was to be able to take a certain amount of money out per month personally. But that isn't a long-term view and it can really slow down growth.

With Grasshopper, we were focused not so much on making money, but on building a great company from day one. There were a lot of months where the company was doing really well in terms of revenue, but my co-founder and I were still living off our savings and keeping all that money in the company to help it grow.

My skill set now is understanding how to run and develop a business whether its Grasshopper, the casino-gaming company I'm working on or the three food trucks I started. I've tried in the past to just focus on one company, but it never lasts for very long -- I think I'll always be looking for something new.

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