You indicate that you have converted each item to personal use. Please see this answer from AmyC.
If you purchase an item and depreciate it over its life span, it's value goes to zero since you are getting a little money back each year. At the end of it's life, it may be no good and you throw it away. No tax consequence. Maybe, something happens and it is in great shape and you can sell it for $2,000. Then you pay taxes on the $2,000.
Some people write off extra depreciation, with bonus depreciation or sec 179 deduction and take most or all of it the first year. They they sell it the second year or trade it in or go out of business, they already got that money early, it has to be accounted for and can increase you tax liability.
