The actual land value that you assigned in the past is now largely irrelevant since you will be selling the property this year and you have taken depreciation deductions based on the value you assigned to the structure. You need to ensure that you add the land value to your basis.
You can add the cost of the A/C unit to your adjusted basis since it was just replaced recently.
I am not certain what you mean when you stated you got the "water heater certified". Regardless, in TurboTax you will report that asset as "sold" (i.e., if you expensed it, your cost basis is $0 and you will allocate a portion of the sales price to it).
