Quantity   Component name
1 × Wemos D1 Mini (or equivalent) Any ESP8266 board can be used if you adapt the assembly instructions
1 × Digitally controlled relay shield for D1 Mini (or equivalent) Current capacity is not too important
1 × M5Stack Atom Lite module One per location
1 × BME280 climate sensor (optional) Any I2C climate sensor
1 × Push-button momentary normally open switch (optional) You only need this if you want a local button on the box holding the relay
1 × Mini breadboard The tiny kind with 170 holes; about 1.5 x 2 inches
16 × Long male pin header strips 2 strips of 8 pins. You want to have a "tail" length of at least 20 mm or so
1 × 3D printed enclosure The device isn't that large, so you could probably adapt an off-the-shelf project box
1 × USB power supply for Wemos D1 Mini