Check the prior year tax return for IRS Form 4562, as that will show the depreciation for that tax year. If you have that form and there's an amount on line 19h, then the property has most likely been depreciated as required.
I assume you are referring to the screen that asks for COST and COST OF LAND.
COST - What you paid for the property when it was originally purchased.
COST OF LAND - The amount in the COST box that you are allocating to the land.
For example, if you paid $100,000 for the entire property, the COST would be $100,000
If the value of the land is $30,000, then you enter $30,000 in the COST OF LAND box.
After that, the program (not you) will subtract COST OF LAND from the amount in COST to arrive at the value of the structure to be depreciated. Using my numbers above, the program would subtract $30,000 from $100,000 to arrive at a structure value of $70,000. The $70,000 is what would be depreciated over the next 27.5 years.
