1) Items $200 and less are deducted.
2) If you make the election, do NOT enter those items as Assets. Enter them as deductible expenses. If you make the election, ALL items that qualify must be entered as deductible expenses, and you CAN'T depreciate those items.
3) Yes, UNLESS you wanted to use Section 179 on some items, and use regular depreciation for others. If you use the De Minimis election, ALL items that qualify must be deducted.
Although there is no way the IRS can prove you did not do this, there is another requirement to make the De Minimis election. It must have been your 'policy' since the beginning of the year to deduct items under a specific amount for your non-tax purposes (for your 'books'). In other words, on or before January 1st, 2016, you needed to have made the decision "Hey, I'm going to deduct items under $2500 for my 'books'", otherwise you don't qualify for the election.
Actually, it's not necessarily $2500. It is UP TO $2500. Your decision to deduct those items for your 'books' can be for a different amount. For example, if your decision was to deduct items under $1500 for your 'books', then the De Minimis election can only be used for items under $1500.
