Over the course of eight years, I went from being $300,000 in debt to making my first million. 

As I took more ownership of my finances, I realized that I felt broke a lot of the time, in large part because I was making several money management mistakes that were actually costing me more in the long run. 

Today, when I work with my financial coaching clients, I make sure to warn them away from overspending on four common missteps that too many people make — and what to do instead.

1. Annual credit card fees

A lot of credit cards with annual fees aren't worth the cost. Unless you're maximizing travel rewards, cash back or other perks that are valuable to you, you may just be handing free money to credit card companies.

If you have a high-fee card, do the math. Are you getting more value than what you're paying? If not, downgrade or switch to a no-fee alternative.

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I only have two credit cards: One for personal use, and one for business use. Though I do tens of thousands of dollars in transactions per month, neither of them is a card with annual fees or perks.

To me, being able to pay off my credit cards weekly, not just monthly, far outweighs the benefits of a card with an annual fee. 

I go online to pay my balance every week — sometimes more than once a week if I'm traveling a lot! I find that by paying off my credit card weekly, I'm able to focus more on my actual spending, versus how many points I'm earning.

2. Financial advisor fees, especially when you're younger

Many of my coaching clients didn't realize that financial advisors charge a percentage of your money, often 1% of your portfolio annually. That might not sound like a lot, but over decades, it can cost you hundreds of thousands of dollars in lost growth.

Besides, financial advisors are often not as useful in the wealth accumulation phase as they are in the retirement phase, when you need to look at tax-saving strategies and optimal ways to liquidate investments. 

If you need investment advice, consider a flat-fee advisor or a one-time consultation instead of ongoing management.

3. Overpaying taxes by not using retirement accounts to invest

A lot of people invest in a brokerage account before maxing out tax-advantaged options like a 401(k), IRA, or HSA. That means they're paying more in taxes than they need to.

Many of my coaching clients did not understand that they could invest in the exact same things in an IRA as they could in a brokerage account. Once I told them the difference involved paying more taxes, they made the switch.

Take advantage of retirement accounts first to maximize tax benefits. Unless you have put the maximum allowed by the IRS each year in these, you likely don't need a brokerage account at all.

4. High expense ratios on investment funds

Most people don't check the expense ratios on their 401(k) or mutual funds, but these fees eat away at your retirement investments over time. While paying an extra 1% in fees might not sound like a big deal, over 30 years, it could mean losing out on six figures in potential growth.

Unless you're a professional investor who will spend a significant amount of time managing your investments, low-cost index funds instead of high-fee actively managed funds are a simple swap that can save you thousands in the long run.

Overall, if you want to take a closer look at where to save more money, start by investigating one of these four areas. You might be surprised by how a small change can affect how much you can invest toward your future financial independence.

Bernadette Joy is the author of "CRUSH Your Money Goals″ and a personal finance expert and investor dedicated to helping you beat burnout and reach financial independence. You can find her on Instagram, YouTube and LinkedIn.

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