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Not really sure what you're asking. Starting a business doesn't require credit unless you're planning to borrow the money to do it. Is that what you're asking? If so, I would strongly recommend that you do NOT fund business activities with personal credit. It is a dangerous road that I traveled and it cost me dearly. It took me seven long years to recover from that mistake.
If you have to personally guarantee your business credit then you need to get your personal credit in shape. All of the usual stuff applies. Keep in mind that if your credit profile doesn't support extending more credit to you then you won't get approved. With only 16 months and 9 accounts you probably still have a relatively thin profile and may have difficulty getting more credit extended to you.