About rental properties and donation

1- I bought a rental property in 2021. While filling expenses for rental property for the year 2021, I entered $ 15k. These expenses were part of closing cost. However there is another section in "First time rental" which asks for expenses as part of closing where the $ 15k entered before is part of it. I believe the system has summed up the same thing and has raised the overall cost of the house for depreciation. So for expenses, should I give priority to overall 2021 expenses or account for expenses as part of closing costs?

 

2- For depreciation, land cannot be depreciated but house can. So how much % of the entire cost of the purchase price of the house shall be land value? By the way, the appraisal document does not have the land and improvement cost split in it. And what does the improvement value of the house mean?

 

3- I am a single person filing just for myself. What is the maximum donation amount that I can file without the IRS asking for receipt?