I understand your question is how to deduct home office expenses in your LLc taxes. If you have a single member LLC it is treated as an ignored entity and you enter the information on schedule C of form 1040. I suggest you open a bank account in the LLC name to record all the LLC income and expenses. It is much easier not to miss expenses if you pay all of the business expenses from the LLC bank account. Do not pay personal from the LLC bank account. Take distributions, but do not pay personal expenses. You must also keep all receipts. I suggest you adopt an accountable plan with the LLC. You can google accountable plan to see what would work for you. With respect to auto expenses you need to keep a log of total miles for the year and business miles. For home office you need to have a separate room that you use solely in the LLC business. You need to allocate the expenses based on square footage. Also take a look at IRS instructions for form 8829. See link below: https://www.irs.gov/forms-pubs/about-form-8829
