If you have zero accounting units and need some more business courses, the Masters route may not be enough so your best course is to get another bachelors in Accounting. If your education in in US, it's more likely you will not have to retake those core courses and can use your other units as electives to satisfy the degree requirement, and you'll only need to take the Accounting and Business courses for a second degree.
Most jurisdiction requires 24 semester hours of accounting courses at the upper division level (junior level courses or higher), and additional 24 semesters hours of Business courses.
Depending what State is your residence, it is most economical to enroll in a University in your home State to take advantage of the In-State tuition. Or if you plan to take courses online, there are several Universities that offers online degree in Accounting and most offer in-state tuition if you are only taking the courses online.
Here are a few Accredited Universities offering online Accounting degree: (In-State Tuition rate for online route)
BBA Accounting at Georgia SouthWestern State University – $199 per credit hour.
BA Accounting at Clayton State University – $220 per credit hour.
BBA Accounting at Chadron State College – $279 per credit hour.
BSBA Accounting at West Virginia State University – $301 per credit hour.
BS Accounting at Athens State University – $309 per credit hour
BS Accounting at Southern New Hampshire University – $320 per credit hour.
Good luck with your search.
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