Jan 15th: Project costs is something I am always trying to always reduce. Currently I have not found UL1015 wire in short lengths and only in 100' spools. Also having wires in different colors always make wiring the project easier is not a requirement. I originally spent $75 for three(3) spools of the UL1015 wire (16awg red and black, 18awg white) so that everything would be color coded and make wiring into my home wiring straight forward. In high sight I could have gotten away with just one(1) spool of 16awg and then just had to clearly label each wire.
Another area would be to eliminate the LED switch breakout since it would get another $1-2 and just makes wiring everything up a little easier. Near term I plan to keep the breakout but it will be something I mention as being optional.