First up was seeing what's going on with power monitoring gadgets these days. I knew there were a lot of smart outlets available. I already have several. A couple are hard-wired into the walls, but most are plug-in type adapters that I can move around. Although I have a lot of these, I only use a couple (aside from holiday time, when I use them to turn the decorative lights on and off). 

I was amazed at the variety of smart outlets that also include energy monitoring. I was further amazed at how reasonably priced they were. I went on a web windows shopping expedition with the optimization inputs of price, company reputation, and ease of integration. After clicking around for an hour or so, the easy choice for me was ....

The Sonoff S31 is an aesthetically pleasing smart outlet with power monitoring. A pair of them can be plugged into a standard US duplex power outlet. (Its sibling, the S31 Lite is cheaper but does not include power monitoring.) Sonoff is popular in the DIY community. The S31 is widely available for under US$10 (I bought a 4-pack for under US$40). It communicates over wifi. This article, though a few years old, has a lot of good technical detail about the S31.

Perhaps the most important thing for me was that the controller inside is an ESP8266, which meant it was pretty likely that I could put ESPHome onto it. Even without being completely sure, I ordered some and waited.