I bought these little 433 mhz receivers and transmitters off of ebay for dirt cheap. I used the receiver to record the fan command signals. The ESP listens to MQTT messages from Home Assistant and sends the signals to my ceiling fan accordingly. Happy to share the code if there's interest!

This was printed with white Yuaneang PLA (cheapest filament I found on Amazon) at 200 C, 0.2 mm layer height at 60mm/s. This was also one of my first attempts at using the sharpie filament color model by Diggle.