You are correct. It is IMRAA. Slight modification . . . it will touch Part C (Advantage), too.
The OP should check with an accountant and find ways to allocate costs to those rental unit sales. Drag the income down.
It’s only for 1 year, too, presuming the next year won’t have more units sold for big gains.
Yes, and it will impact Part D drug premium, which go from zero when you are paying the $185 this year ...to an extra $13.70 monthly per person... or an extra $85.50 per person in 2025 for the $750K plus earners! The taxman gets his cut on the onetime windfalls... ymmv