I have just completed a project for the control of an 8 Channel Relay board which runs up to 8 rope lights each 240VAC.
Here are a couple of images showing the elements of the project.
Apart from the purchase of the Arduino board and an 8 Channel 5V Relay board ($17US) the only other items that needed purchasing were 1 x 10 metre and 8 x 3 metre extension leads. I also purchased a case for $26.00 and 9 Cable glands to keep the project tidy.
Overall the project was great fun and surprisingly inexpensive.
The case is to be located in a protected area as even in the best conditions the case isn’t waterproof.