How is foreign investment property income handled with HSP Visa income and then PR?

I have been granted an HSP Visa through Deel’s EoR as a US tech worker. My salary through the HSP Visa is $375,000 USD per year.

I am planning to get PR after the 1-3 years, and hopefully then just simply quit work and retire.

We have 18 residential properties located in the US (clear and free, no mortgage and no debts) managed by a firm and they simply just send us a $35,000 USD check every month. So about $420,000 USD per year from that.

I’m not sure how this rental income is taxed during my Visa and then afterwards?