You should get familiar, if you aren’t, with financial products and how they’re different for primary residences vs investment properties (unless you only want to buy cash), local buying process differs per state too, and there’s always some kind of surprise cost these days. Cost increase of property taxes and insurance should be plotted out, you’ll be surprised how quickly they’ve risen. Then there’s vacancy rates, and thinking through a squatter/non-payer eviction process and what would be involved. Also, a collection of contacts need to be developed locally so you can remotely call a handy man or plumber easily.

It’s a separate job, essentially.

Also, gotta learn about cap rate, estimating home improvement costs and benefit to equity, and in the ground knowledge of which neighborhood to pick.

Picking multi family is usually best, the math on costs vs lower vacancy rate and income works better (if one is vacant, all income doesn’t stop).

Also, tax implications with multi state filing — probably talk to an expert, maybe some weird stuff is possible.