If  you the Online version of TurboTax, you must use TurboTax Premier to enter the sale of your second home.  If you are using the CD/Download version, you can use TurboTax Deluxe, but there is more guidance in the Premier version.

A sale of a second home is considered a sale of an investment.  To report this in TurboTax, please follow these steps:

TurboTax Online

1. Click on Federal > Wages & Income
2. In the Investment Income section click on the Start/Revisit box next to Stocks, Mutual Funds, Bonds, Other.  If you have already entered some investment sales, you will see a screen Here's the investment sales info we have so far.  Click on the Add More Sales link. 
3. If you haven't yet entered some investment sales, you will see a screen Did you sell any investments in 20XX?  Click the Yes box.
4. On the screen,  OK, what type of investments did you sell? mark the Other box and click Continue.
5. When you get to the screen, Now we’ll walk you through entering your sale details enter the details of the sale.  You will be able to select the type of investment in the first box [second home, land, etc.]  [See Screenshot #1 below.]
6. Enter the requested information and click Continue when done.

TurboTax CD/Download

1. On the Wages & Income screen, in the Investment Income section click on the Start/Revisit box next to Stocks, Mutual Funds, Bonds, Other.  If you have already entered some investment sales, you will see a screen Here's the investment sales info we have so far.  Click on the Add More Sales link. 
2. If you haven't yet entered some investment sales, you will see a screen Did you sell any investments in 20XX?  Click the Yes box.
3. On the screen,  Did you get a 1099-B or brokerage statement... click the No box.
4. On the screen, Tell us about this sale, mark the radio button, I'll enter one sale at a time.
5. Enter the information in the boxes that appear.  You will have to type in Second Home in box 1a.
6. Enter the total sales proceeds as well as the other information requested.  [Screenshot #2]
7. Continue to the screen, Select any less common adjustments that apply.  
8. Mark the first box The reported sales price did not deduct all fees or selling expenses.  [Screenshot #3]  
9. Enter the sales expenses not deducted from the sales price entered earlier.

Screenshot #1

Screenshot #2

Screenshot #3

Thank you for taking time to respond to my question, it was very helpful! I'm working with the windows CD version of TT deluxe. Before I got the the screen shown in your screen shot #2 it wanted the name of a financial institution and that threw me but I told it to delete the empty entry and the screen shot #2 page came up. I do have a question about how I enter the value of the updates that were done to the condo and the various cost of sales items. It looks like I enter what we sold the condo for in the box 1D and what we bought the condo for in box 1E and then enter the cost of the various improvements we made plus the various fees and commissions in the entry shown in your screen shot #3?  Thanks again for your help.

Almost!  Add the cost of the improvements to what you paid for the property and enter in box 1e (cost or other basis) and then the various fees and commissions in the box in screenshot #3.

another question, I put the Sales proceeds box  1D as $210,000 and the Cost or Other Basis box 1E as $122,172 and put it as a long term and the Federal tax went to zero. The next screen looked something like your #3 screen shot but there wasn't a place for the fees and commissions. I don't understand why the federal tax went to zero, there should be something to reflect the profit shouldn't there be? Sorry to be such a pest but don't want to report this wrong. 

Even though you did have a gain on the sale of the property, if you had capital losses also reported on your return then your gain would have been reduced.  Since your gain was long term, it is possible that your tax rate could be 0% depending on the other income reported on your return. 

If part of your taxable income is due to long-term capital gains or qualified dividends, then your tax amount is not determined strictly by using the Tax Tables.  Qualified dividends and capital gains are taxed at a lower rate and therefore your overall tax may be lower.    

The worksheet used to calculate your taxes when taking capital gains into account is found in the IRS Instructions for Form 1040.  It is called the Qualified Dividends and Capital Gains Tax Worksheet.  This worksheet will be included as part of your tax return if it is being used to calculate your tax.  

You can also find it on page 35 of the PDF document at this link:  2020 Form 1040 Instructions

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