Yes.
Charging on a credit card is the same as paying cash. That is the date you purchased it.
You purchased the computer in 2021.
No, it is not an "Expense" because it is a tangible THING. You may be able to take the 179 Deduction which results in the same as expensing. The entire amount is deducted from your business income.
Look for Form 4562 from your 2019 Tax Year Return for 179 deduction, Bonus Depreciation and Straight line depreciation on assets.
When the computer changes from business to personal use only, you need to be aware of the depreciation you took on it.
IF you were to sell it, you might need to repay that depreciation back as "Depreciation Recapture" and it is taxed at your regular income rate. If it becomes useless, it is at the end of it's life.
Again, changing from all business to 50/50 would not require any reporting if you fully depreciated it the year it was placed in service. Again, if you were to sell it, you would need to recapture the depreciation.
Also be aware that you cannot use the 179 Deduction for more than your income for that year.
If you do, it is lost.
For example, say your only income is Self-Employment and that income is 10,000.
If you try to do a 179 for 15,000 worth of assets, you'll get 10,000 against your income and the remaining 5,000 is lost. It will not carry over.
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