I think the IRS treats rental property income as passive if you can't document 750+ hours or something like that managing the property. This is actually bad news because:
1. You can't offset your cap losses in stocks with rental gains.
2. Rentals in my experience are anything but passive. Tons of stress managing your property managers.
For passive rentals nowadays, I prefer to invest in syndications.
I don't think there's anything as 100% truly passive. For example, you do a real estate deal and you spend a month getting a rental. And then perhaps you manage your PMs 2 hours/month. After 10 years, you can amortize that month of effort + 2hours/month effort and end up with some $/hr. Sure, you'll get some high $/hr over 10 years but 100% passive means it's 'infinite' -- and all 'passive income' takes some maintenance.
Take another example: I wrote a bot that arbs NFTs. It earns money but took 2 months of very difficult effort to do. And it takes some maintenance to update the code because 1) there are more and more competitors everyday / margins are getting squeezed, and 2) sometimes there's bugs that crash the server and you gotta go fix it. So maybe I spend 1hr/week maintaining this 'passive' source of income. But I also spent 2 months of like 12 hours a day developing the bot. So it's like: even after 2 years, I've spent 2/24 months working + 1hr/week maintaining for 22 months = 88 hours + 2 months of work = 3 months of work over 2 years. It's not '100% passive' by any means but if the maintenance effort is low enough and you enjoy the work, I'd consider it 'somewhat passive'.
