Commercial is hard to break into in large cities - high cost being a big barrier. Multifamily are one option, depending on the tenancy laws where you are.
I'd recommend looking at mini-storage properties. That was my path in, and it can be excellent.
The best thing about commercial real estate is that it is much more hard nosed that residential. What I mean is that a commercial property is mostly just worth a multiple of what you can make from it, and you can scale your price using that metric. There is no premium for a view or being close to a school for a warehouse.
That can make for some funny bargains. My first commercial property had 34 storage units, 8 one-room office units and 2x2 br apartments. I could not have bought a duplex for what I paid for the entire commercial property, and it came with 42 other paying units. Granted, it needed a lot of work (1.5 yrs of renovations) but the upside was enormous. Because it was commercial and I am in a smallish town there was very little competition for the property and I got it at a 12% cap rate. This is not normal, but it is something to look for because they do happen.