reg 1.179-1(e)
(e) Change in use; recapture -
(1) In general. If a taxpayer's section 179 property is not used predominantly in a trade or business of the taxpayer at any time before the end of the property's recovery period, the taxpayer must recapture in the taxable year in which the section 179 property is not used predominantly in a trade or business any benefit derived from expensing such property. The benefit derived from expensing the property is equal to the excess of the amount expensed under this section over the total amount that would have been allowable for prior taxable years and the taxable year of recapture as a deduction under section 168 (had section 179 not been elected) for the portion of the cost of the property to which the expensing relates (regardless of
whether such excess reduced the taxpayer's tax liability). For purposes of the preceding sentence (i) the “amount expensed under this section” shall not include any amount that was not allowed as a deduction to a taxpayer because the taxpayer's aggregate amount of allowable section 179 expenses exceeded the section 179(b) dollar limitation, and (ii) in the case of an individual who does not elect to itemize deductions under section 63(g) in the taxable year of recapture, the amount allowable as a deduction under section 168 in the taxable year of recapture shall be determined by treating property used in the production of income other than rents or royalties as being property used for personal purposes. The amount to be recaptured shall be treated as ordinary income for the taxable year in which the property is no longer used predominantly in a trade or business of the taxpayer. For taxable years following the year of recapture, the taxpayer's deductions under section 1688(a) shall be determined as if no section 179 election with respect to the property had been made. However, see section 280F(d)(1) relating to the coordination of section 179 with the limitation on the amount of depreciation for luxury automobiles and where certain property is used for personal purposes. If the recapture rules of both section 280F(b)(2) and this paragraph (e)(1) apply to an item of section 179 property, the amount of recapture for such property shall be determined only under the rules of section 280F(b)(2).
(2) Predominant use. Property will be treated as not used predominantly in a trade or business of the taxpayer if 50 percent or more of the use of such property during any taxable year within the recapture period is for a use other than in a trade or business of the taxpayer. If during any taxable year of the recapture period the taxpayer disposes of the property (other than in a disposition to which section 1245(a) applies) or ceases to use the property in a trade or business in a manner that had the taxpayer claimed a credit under section 38 for such property such disposition or cessation in use would cause recapture under section 47, the property will be treated as not used in a trade or business of the taxpayer. However, for purposes of applying the recapture rules of section 47 pursuant to the preceding sentence, converting the use of the property from use in trade or business to use in the production of income will be treated as a conversion to personal use
what is the recovery period? you didn't provide enough info. in 2017 did the half-year convention or mid-quarter convention apply
The mid-quarter convention. Use this convention if the total depreciable bases of MACRS property you placed in service during the last 3 months of the tax year (excluding nonres-idential real property, residential rental property, any rail-road grading or tunnel bore, property placed in service and disposed of in the same year, and property that is being depreciated under a method other than MACRS) are more than 40% of the total depreciable bases of all MACRS property you placed in service during the entire year.
Under this convention, you treat all property placed in service or disposed of during any quarter of the tax year as placed in service or disposed of at the midpoint of that quarter. This means that, for a 12-month tax year, 1-1/2 months of depreciation is allowed for the quarter the property is placed in service or disposed of.
If you use this convention, enter “MQ” under column (e) in Part III of Form 4562.
if mid-quarter doesn't apply then half-year convention applies
with the half-year convention the recovery period for the vehicle is from 7/1/2017 through 6/30/2022 (5 full years)
with the mid-quarter convention the recovery period for the vehicle is 10/1/2017 through 9/30/2022 (5 full years)
