Instead of depreciating certain expenditures, you may be able to use an IRS-created de minimis safe harbor to deduct these costs (up to $2,500 per item or invoice). You can find more about the safe harbor from the IRS at https://www.irs.gov/businesses/small-businesses-self-employed/tangible-property-final-regulations. Also keep in mind that in 2018, you can use 100% bonus depreciation to write off the full cost of equipment and machinery as well as certain capital improvements to commercial realty.
Tax paid by self-employed persons to finance Social Security coverage. In 2007, there are two rates. A 12.4% rate applies to a taxable earnings base of $95,700 or less and a 2.9% rate applies to all net earnings.