The business expenses you incurred for your phone, IMusic, supplies, etc., are deductions you may take in full to reduce net income subject to self-employment tax. If you use your vehicle for part business and part personal, the Standard Mileage rate would only apply to your business mileage and that amount used to reduce income subject to self-employment tax. Car washes, maintenance & repairs, gas, etc. would only be deductible if you chose actual expenses rather than the Standard Mileage rate.
Please comment if you need additional assistance with this.
