Money Mistakes that Cost Business Owners Big Time

What are the common financial/money mistakes business owners make that cost them a lot? How can they prevent/avoid making these mistakes? What should a business owner NOT do when it comes to managing their finances? Pitches from business owners, lenders, finance professionals, lawyers, accountants, bankers, investors, university professors, and other professionals with related experience and expertise. Please send your answers directly when you reply. Also include your full name, position, company, website, and a link to your headshot photo. Include a one-paragraph explanation per tip. You can give as many tips as you want for higher chances of getting featured in the article.