Question

How do I get Turbotax to properly report the sale of fine art?

A capital gain on the sale can't be reported as a normal capital gain, so it needs to be reported as a fine art sale.

Net capital gains from selling collectibles (such as coins or art) are taxed at a maximum 28% rate.

To enter your fine art sale as a Collectible:

Log-on to your TurboTax.
Select Pick up where you left off.
On the left side menu, select Federal then Wages & Income.
On the Your income and expenses screen, scroll down to Investments and Savings (1099-B, 1099-INT, 1099-DIV, 1099-K, Crypto) and Edit/Add.
If you get the Your investments and savings screen, scroll all the way down to +Add investments.
Continue until you get to the Let's import your tax info screen and select Enter a different way.
On the OK, let's start with one investment type screen, select Other (1099-S) and Continue.
On the Tell us more about this sale screen, enter the information.
On the Now, enter one sale for XXX screen, in the What type of investment did you sell, select Collectible from the drop-down menu.
Continue entering the other information until complete.