Expense can only be taken on business portion (ie if you claim 80% business use, section 179 expense = 80% of the cost). 100% business use might be questioned, especially if another computer isn't available for personal use.
I've heard of certain items you can get an out and out tax credit for. Like John Stosile who used to be at ABC and moved to Fox described a transaction where he bought a small electric vehicle for about $7000 and that was directly deducted from the taxes he had to pay, so it was basically free.
I'm not sure if that works like the home credit, where $8000 is even given as a direct cash payment, even if you don't pay any taxes.
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