You aren’t doing the rest of the math. That duplex has maintenance, taxes and lost occupancy during rental transition. Once you factor in all the shit you missed you end up with either a break even or more likely cash flow negative position. At that’ point all you are just gambling on continued appreciation of the property, and hoping you can make up the 10% in transaction costs. In the past that’s been a decent bet but who knows. Current interest rates and demographic are working against you at some point affordability might come to bite. Or it might not and more people will just have to cram into tighter spaces. If you were to just rent that 2200$ unit you would save 2-3k a month and you could invest that instead. Overall the risk of investing the savings in diversified equities is lower than that of buying into a single housing asset, but of course there are no guarantees.