The qualified business income deduction applies only to a trade or business. Under an IRS-created safe harbor, a rental real estate activity may be treated as a trade or business for purposes of this deduction. Details of this safe harbor are in IRS Revenue Procedure 2019-38 (https://www.irs.gov/pub/irs-drop/rp-19-38.pdf).
Advance payment of current tax liability based either on wage withholdings or installment payments of your estimated tax liability. To avoid penalties, you generally must pay to the IRS either 90% of your final tax liability, or either 100% or 110% of the prior year’s tax liability, depending on your adjusted gross income.