TurboTax H&B 2020 makes it less than clear, in my opinion, about how a rental property converted from a personal residence should be handled in disposition, but apparently it can't be done through Step-By-Step.
It most certainly can be done via step-by-step. Two issues.
1) Most people don't read the small print on each screen as they work it through. This becomes obvious when they inform us they marked the property as sold, but were never asked for sales price information.
2) In my personal opinion (and we all know what opinions are like) the program does not provide the necessary clarity on the data entry screens for even a "basic" sale of rental property. Especially if that property has more than one asset listed in the assets/depreciation section for that property.
Here's the basic guidance for a "simple" sale (which is what you appear to have, based on the information you have provided thus far).
Reporting the Sale of Rental Property
If you qualify for the "lived in 2 of last 5 years" capital gains exclusion, then when prompted you WILL indicate that this sale DOES INCLUDE the sale of your main home. For AD MIL personnel who don't qualify because of PCS orders, select this option anyway, because you "MIGHT" qualify for at last a partial exclusion. Take note here @JeffV that you do not qualify for the exclusion since the property was not your primary residence for any period of time during the last 5 years you owned it, counting backwards from the closing date of your sale.
Start working through Rental & Royalty Income (SCH E) "AS IF" you did not sell the property. One of the screens near the start will have a selection on it for "I sold or otherwise disposed of this property in 2020". Select it. After you select the "I sold or otherwise disposed of this property in 2020" you continue working it through "as if" you still own it. When you come to the summary screen you will enter all of your rental income and expenses, even if it's zero. Then you MUST work through the "Sale of Property/Depreciation" section. You must work through each individual asset one at a time to report its disposition (in your case, all your rental assets were sold).
Understand that if more than the property itself is listed in your assets list, then you need to allocate your sales price across all of your assets. You will only allocate the structure sales price; you will NOT allocate the land sales price, since the land is not a depreciable asset. Then if you sold this rental at a gain, you must show a gain on all assets, even if that gain is $1 on some assets. Likewise, if you sold at a loss then you must show a loss on all assets, even if that loss is $1 on some assets.
Basically, when working through an asset you select the option for "I stopped using this asset in 2020" and go from there. Note that you MUST do this for EACH AND EVERY asset listed.
When you finish working through everything listed in the assets section, if you ever at any time you owned this rental you claimed vehicle expenses, then you must also work through the vehicle section and show the disposition of the vehicle. Most likely, your vehicle disposition will be "removed for personal use", as I seriously doubt you sold your vehicle as a part of this rental sale.
