I built a 2-Relay version using one of the cheap relay shields (http://www.amazon.com/JBtek®-Channel-Shield-Arduino-Raspberry/dp/B00QGUFVWU) and an RGB LED. I wanted to power it with 12V so the same supply could also be used for motorized ball valves for house water control. To get reliable operation, I needed to use two of the little 1117 5V boards, one for a nodemcu board and one for the relays. I also needed a power resistor to drop the supply voltage to the regulators. A 12 ohm 5 watt resistor is giving 10.8V to the boards with both relays off and 9.4V with both relays on. Might be able to use a single regulator board with a bigger resistor to lower the voltage even more, but I haven't tried.