As a tech entrepreneur and head of the New York Angels investing group, Cohen has been on both sides of the negotiating table. His advice? Focus on relationships.

If the founders have a poor relationship, is the company doomed?

Most of the time, because it usually can't be fixed. I met a bright group of people whom I was really interested in investing in, but I didn't. They had terrible chemistry, and I knew from the start it was going to be a problem. And bingo! It was.

What's one sign of a great team?

The ability to be happy for one another. You want people who are going to applaud one another, not be jealous of one another.

What's the biggest mistake you see in entrepreneurs' pitches?

Too often they say, "Let me show you what our product does." I want to know how you're going to build a company, and I want to know whether you really know your customers. That relationship is key.

Speaking of relationships, you founded one of your first companies, Technology Solutions, with your wife. How did you make it work?

It wasn't easy. There were moments when somebody had to say, "I'm in charge," and somebody had to give. I'm lucky I married a strong woman. It was hard, but she stuck with me. I knew she was the most brilliant woman I had ever met, and I always let her know that. That said, we don't invest in companies that have husbands and wives as partners!

What can younger entrepreneurs learn from older generations?

Entrepreneurs shouldn't be totally, absolutely driven by passion. I'm passionate about my kids and others I love. Business isn't about passion. Too many kids tell me, "I don't know if I'm passionate anymore. What should I do?" I say, "Find the problem that a customer needs solved and solve it. Build a business around it. Screw passion."

And if they need money?

There's no perfect model that fits everybody. It takes strategy and a feel for when it's the right time. We'll tell you if it's not quite ripe. We want to give you smarter money.