Sale of rental property, missed renovation basis, and additions before sale

Your capital improvements should have been entered as separate assets for the tax year you made the improvements.  Those assets, as part of the rental property should also have been depreciated.  You do NOT just add them to your cost basis.  When you calculate the gain (assuming you have a gain) on the sale, you have to calculate depreciation recapture for all the depreciation taken, or eligible to be taken.  That means you have to include the depreciation you could have/should have taken on the capital improvements, even though you didn't deduct it as an expense in previous years.

There is a work around for this. You can file Form 3115, Application for Change in Accounting Method and take all the missed the depreciation on your current year return.  While you can file Form 3115 with TurboTax, it's not a simple form.  For more information see the following IRS website:

About Form 3115, Application for Change in Accounting Method 

As for the land value, you should have added that when you initially set up the rental property.  If you did not allocate a portion of your cost basis to the land when you set it up, you will need to adjust your original cost basis and depreciation via the Form 3115.  The typical way to allocate costs and sales proceeds between the structure and the land by using the ratio of land to improvements on your property tax bill.  You then take that ratio and apply to the actual cost and do the same for the sales proceeds.  You would use the property tax information for 2001 for the cost allocation and the 2025 bill for the sales allocation.  

You will report the 2025 rental income and expenses the same way you would in a full year rental.

If it was me, I would file an amended return for 2024 with Form 3115 and get everything set up correctly with the correct accumulated depreciation amounts.  Then I would file 2025.  That would require filing an extension for 2025.  You wouldn't want to file 2025 until you had confirmation that the IRS had accepted your changes on the amended return.