If you use property both for business and personal purposes, you may deduct it under Section 179 only if you use it for business purposes more than half of the time. Reduce the amount of your deduction by the percentage of personal use. You'll need to keep records showing your business use of such property. If you use an item for business less than half the time, you must depreciate it.
我知道这可能受很多因素影响，我啰嗦一点尽量把情况说清楚些。
现在做着一个full time 工作，同时管着十几个出租房。每年报税出租房都有正收入（如果lease一辆车抵税后也会是正收入）。出租房大多三四十迈远。现在报税只是报些里程数抵税。我想lease一辆车，这辆车除了跑出租房，还会用于上班和日常交通，但每年里程数不会超过一万迈。我想以出租房的名义把lease的费用全部抵税，这样做风险大吗？我会说我有另外一辆车私用（老婆的车在我的名下）。车的保险也可以抵税吗？没开LLC，有real estate license，如果把lease 费用抵税是把费用分摊给十几个出租房，还是算成self employee的费用比较好？我的license主要是给自己买房用，还不知道2023年会不会开张。如果把lease 费用用self employee抵税，这一项可能就是负数了。如果分摊给出租房，出租房总收入还会是正的
多谢指点！
https://www.nolo.com/legal-encyclopedia/section-179-expensing-rental-property-owners-deduct-long-term-asset.html
If you use property both for business and personal purposes, you may deduct it under Section 179 only if you use it for business purposes more than half of the time. Reduce the amount of your deduction by the percentage of personal use. You'll need to keep records showing your business use of such property. If you use an item for business less than half the time, you must depreciate it.