probably all of it. either the item will meet the de minimus exception and thus can be expensed directly or for other items, you can take section 179 depreciation (limited to business income before this deduction) or section 168(k) special depreciation (not limited to business income). however, the question is it prudent to take all the write-offs allowed in the first year. you may end up paying very little tax. because all these deductions wouldn't likely recur the next year you could end up paying a lot of tax in year 2. spreading out the deduction over several years may cost less from in total taxes. it would be prudent to discuss this with a tax pro who could advise you based on actual numbers and your ideas of how the business would do in the future.
