Where can I download the basis calculation that turbo tax does for rental property depreciation?

If you're using TurboTax Desktop, it should have been included in last year's return if you printed (paper or PDF) the entire return.  If you want to see this year's, you can print without filing.  You will need to pay for TurboTax and then you will be able to print your entire return or specific forms/schedules prior to filing.  You will still be able to make changes prior to filing. Follow these steps to print a preliminary copy of our return in TuboTax Online:

• While logged in and working on your return, click on Tax Tools
• From the drop down menu click on Print Center 
• Click on Print, save or preview this year's return
• On the next screen click on "Pay Now" 
• You may be prompted to "Go to My Info" if you need to add additional information
• Submit your payment information and you will be able to print your tax returns

Note, you must pay by credit card in order print or preview your preliminary return.  You will not be able to pay using your federal tax return.

If you are using TurboTax Desktop you can go to Forms view and then select the Depreciation Schedule or the Asset Worksheet, which will show you all the information used to calculate depreciation.   If you are using TurboTax Online, you might want to consider switching to Desktop.  For more information see:  How do I switch from TurboTax Online to TurboTax Desktop?