5 Mistakes to Avoid When Starting Your First Business A new entrepreneur's 'fast-success' launch of a fitness center proved to have some unhealthy aspects.

When I opened my first business, a fitness center, unfounded confidence flowed through my veins. Visions of fast success and weekends off with the family seemed as close as the next sell.

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A few months later, the bravado gave way to fear and insecurity. That dream about weekends away vanished, and my 5 a.m.-to-9 p.m. schedule began taking its toll. I have been fortunate ever since to avoid similar mistakes in my more recent businesses. But I continue to review those mistakes, lest I repeat them:

1. Allowing belief to override the business plan

Owning a business is not for the weak in spirit. You need a strong mind and heart to face the day-in and day-out work. In the early days of the dream, it's easy to be so excited and enamored with the idea of "your" business that you fail to grind out a proper business model.

When I approached my bank with my business plan in a thick three-ringed binder, I thought the president might just hand me a briefcase of cash. No kidding. Then came reality: Within two minutes the bank president asked me several questions my plan couldn't answer. Still, that didn't faze me. I lifted my chin and stated with conviction, "This will work." I left without the briefcase of cash. Belief overrode the business plan, and I exited penniless.

2. Listening to customers instead of spreadsheets

"Famous Health Club just went out of business," my soon-to-be business partner Mike said. "They left all the equipment," he told me excitedly. "We can go in and start quickly and not have to buy everything. However, they scammed their people, and no one wants to sign a contract."

No problem. We won't do contracts, I thought. And we didn't. But we should have. Because, six months later, a giant fitness chain came to town and told members they could sign up for two years and pay via automatic draft. And people signed up in droves. Our "we won't sign a contract" people left for newer pastures.

The lesson is, you'll be tempted to set up your business in the way your customers say they want. And, sometimes that will be fine if it fits your model. Otherwise, trust your spreadsheets. Make sure the math works before giving in on every demand in hopes of making the sale.

Related: 6 Common Mistakes First-Time Business Owners Should Avoid

3. Risking a family member's retirement fund

Remember my empty briefcase? I gave up on the bank and instead went to my grandfather and asked for the money. I needed only $20,000. That's it. It never crossed my mind that Daddy B might consider what I requested to be a big sum, considering that during his career, he'd been a lowly paid high school principal. And, as if that weren't enough, he told me he believed only in safe investments and had put most of his own money into interest-bearing certificates of deposit earning a massive 2 percent interest.

Being young and arrogant, I took my grandfather back to the same bank. Together, we got a secured loan and I was on my way. So, I was able to move forward. But unless your family members have the money to lose, don't borrow against their retirement or savings. They may love you and want you to succeed, but losing their money will haunt you.

4. Miscalculating the time needed to launch

Since those former fitness club tenants had left their equipment, Mike and I figured that we could open quickly. It was already December and we believed we could open by January 1. Just in time for the New Year's "resolution" crowd. Timing-wise, we thought we'd won the lottery.

But, three days prior to opening, we knew we were in trouble. I still can't remember if we slept those last three days. We pushed hard to open the doors. And they opened, but not without our first suffering stress, tears, fears, panic, anxiety and delusions of the greatest business failure ever known to man.

So, set your own grand opening inside a buffer zone. Plan to be ready 10 days ahead of "the" day and you just might open on time, without dread and anxiety.

5. Equating personal experience with business expertise

I began working out at age 12. I was competing in powerlifting and body-building competitions by age 18. In addition to that, I was a personal trainer at a local gym. Certainly all that experience would translate into running a fitness center of my own, right?

Not even close. I knew how to train people, but not retain people for the purpose of growing a membership-based business. You might be a great cook, mechanic, web designer or artist, but that doesn't automatically translate into business acumen. So grab some study courses from Entrepreneur.com and arm yourself for this battle called business.

A couple of years later, Mike and I sold that fitness center. Our buyer was a guy who wanted the space for his karate school. We barely paid off our business loans with the sales proceeds. It could have been so much more had we avoided the mistakes we made starting our first business.

So, remember them, and learn.

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