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The IRS website at this link covers the key aspects of the Qualified Business Income (QBI) Deduction.

The difference between "QBI" and "not QBI" is a QBI business is eligible for a deduction equal to 20% of any income.  So, you generally want your activity to be a "QBI business" if it is eligible. 

Losses from a QBI business or rental property are netted against income from other QBI businesses or rental properties in a given year.  Net QBI business income in a given year gets the 20% tax deduction.  Net QBI business losses in a given year are carried forward to offset QBI in future years, as are suspended passive losses.  All these calculations are performed within TurboTax. 

Rental properties must meet certain tests to be a QBI activity for tax purposes.  The IRS has issued "safe harbor" rules, which means if it meet certain tests the rental property is considered qualified for QBI.  See the IRS article on the rental real estate safe harbor at this link for an overview of the safe harbor requirements.  I've pasted a summary of those here:

"The following requirements must be met by taxpayers or RPEs to qualify for this safe harbor:

• Separate books and records are maintained to reflect income and expenses for each rental real estate enterprise.
• For rental real estate enterprises that have been in existence less than four years, 250 or more hours of rental services are performed per year. For other rental real estate enterprises, 250 or more hours of rental services are performed in at least three of the past five years.
• The taxpayer maintains contemporaneous records, including time reports, logs, or similar documents, regarding the following: hours of all services performed; description of all services performed; dates on which such services were performed; and who performed the services.
• The taxpayer or RPE attaches a statement to the return filed for the tax year(s) the safe harbor is relied upon."

More details are about "rental services" are in the IRS Revenue Procedure 2019-38 section .04 Rental Services. on page 7 of the PDF at this link, including what qualifies as rental services and what doesn't, and making clear that rental services performed by a management company "count".