If you're an Armed Forces reservist, only expenses for traveling more than 100 miles from home to perform services as a reserve member are allowed.
For lodging, meals, and incidental expenses, the amount you can deduct is limited to the regular federal per diem rate. For car expenses, you're limited to the standard mileage rate, plus any parking fees, ferry fees, and tolls.
These reserve-related travel expenses are deductible whether or not you itemize deductions. See
IRS Publication 463 for additional details on how to report these expenses.