It's 5:45 p.m. one recent afternoon at the Miami Beach, Fla., headquarters of Cardone Training Technologies Inc. Founder and sales guru Grant Cardone is about to cut out for the day when he stumbles upon one of his salespeople on the phone with a customer. It's a heated discussion. The customer is on the fence and unwilling to budge over a mere $100. The salesperson has hit a wall and isn't making any progress.

That's when Cardone jumps in to close the sale. Check out the video above to see the interaction. 

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The type of situation depicted in the video happens every day at startups all over the world. To lock in the sale, you have to have confidence in yourself as well as the product or service you're selling. Plus, you and your team need to have what it takes to close big sales -- otherwise your business will die. 

Here are Cardone's five best tips for closing the big sale:

1. Know when to close.

Whether it happens in person, on the phone or over video, a salesperson needs to know when it's right to move from the sales pitch to closing the deal. There's only so much selling you can do. At some point the customer is going to have to tell you yes or no.

"Ninety-two percent of all customer interaction happens on the phone," Cardone says. "Companies must learn to engage, sell and close when the buyer shows interest."

2. Once you're in the 'close zone,' stay there.

Note in the video that once Cardone got on the call he didn't start selling the features or benefits of his product. He was there to close, not to deliver a sales pitch. The customer needs to make up his or her mind.

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3. Be clear with the customer.

In this video you can see that Cardone didn't beg for the business -- he didn't need to. The customer was ready to close but was stuck on the $100. Cardone made it clear the $100 over a three-year commitment wasn't the issue. He put it on the customer to say "yay or nay, yes or no." 

4. If your sales person is having trouble, step in and get it done.

Sometimes someone on your sales team can go only so far with a specific client. If the sales pitch was on point and your employee can't get the client off the fence, sometimes it's best to have an experienced manager step in. The last thing you want to do is lose the business because you weren't able to close it.

"Managers need to get involved in more customer interactions sooner," Cardone says.

5. Be realistically confident.

Sometimes a sale simply isn't meant to be. But if the client is truly on the fence, a little confidence in yourself and your company can go a long way.

"I am not worried about pressuring the customer or appearing desperate," Cardone says. "I know my product is good for people so I am in a hurry to get it to them."

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