Even though I am not a consultant for doing tax assessments, I have some experiences and resources in that field. It is a fact that your tax accountant is best for you as you get his proper services whenever required.
Already you got answer for the first question from which you can easily make decision. Now you have to use a space for the purpose of writing.
Creators of Turbo Tax Software (the one which I am using to complete the filing process) are the one of the largest roadblock to get deduction. Also the office space must be occupied with things needed for writing and the process of administration and management must be related to that only.
Listen when I am saying the word “space” just as against the word “room”. This means that there is no need of separate room for making a home office for writing purpose. IRS mainly says that this space you have to use only for the purpose of making business or trade. This space can be a room or any area which is separated by using any items to identify easily. There is no need to mark this space permanently as working area. Just it is for the purpose of identification that this space is your area for doing writing works. This way you can use it easily for house office deduction.
Can I make some recommendation from one writer to other? Yes easily it is possible. Listen, you have to pay taxes for your writing works. You have to follow all rules and regulations of IRS. So keep in mind that you have to also follow the rules and regulations which are beneficial for you in many ways.
Few people say that working from home office is liable for audit. But I am not that much sure about it. I am keeping all my records clearly and I will not fear about the auditing process.
IRS published their policies regarding home office deduction in PDF format which you can check. I saw many like that but this publication is more useful as it is straight forward related to this subject. Other than this, if you want more information about this particular subject, then you can go through Guide to Small Business Information where you get more valuable information about many deductions.