We will all go through writing a business letter at least once in our lifetime. It does not matter if you are an employee, an owner, a stay_at_home mom (or dad) that has her own business at home; we all have to go through writing it. It cannot be avoided!
Your cover letter format is very important to your success. With a high quality motivation letter, your chances at getting an interview will dramatically increase. Don't take shortcuts. Pay attention to both what you say (content) and how you say it (format). Your efforts will pay off in your career success!