Your land value is 31% of what you paid for it. Period. Renovations come in later.
So using your numbers (which are not spot on because sales expenses have not been tken into account yet, of course.) when working through the asset you'll have something close to $180,000 in the COST box and $55,800 in the COST OF LAND box. The program will "do the math" in the background *for you* and will depreciate a structure value of $124,200 over the next 27.5 years.
Then you will click "Add An Asset" to add your property improvements which of course, will have *NO* land value, meaning you'll enter $70,000 in the COST box and a ZERO in the cost of land box. That full $70K will then be depreciated over 27.5 years.
So in the end because of the property improvements, your "land to structure" ratio won't be anywhere close to the 31% for land represented on your tax bill, and with your 70K of property improvements I wouldn't expect it to be either. In fact, I would question you as to "why?" with, after 70K of property improvements, your land value wasn't significantly "less" than 31% of the total cost basis.
Please note that the property tax values are only used by the program for establishing a somewhat realistic starting point. It's not like the IRS is going to check. But by doing it that way if you're ever pulled from one of those "random audits", you've at least got something to show the why and how you established the land/structure cost you used.
