Auduino/SSR Board Question

I am working on some simple controllers for holiday lights. Im needing several boxes around my yard with 8 relays inside. Rather than buy mutiple arduinos and run usb cables all over my yard, or run tons of power cables over my yard. Im wondering if I can use cat5 cable to run signal from arduino to the relay. I thought about connecting a female cat5 plug to both the SSR relay board and one to the arduino and then using a patch cable plugged in between them. Would this work? It would give me the flexablilty to expand and reduce the cables needed. Any advice would be great! Thanks.

I would avoid running Arduino signals and mains power down the same CAT cable. You will very likely get interference problems.

The power to the ssr board will be a 5v transformer, I would just be using the cat5 foor communication between arduino and relay. Would that be ok?

The power to the ssr board will be a 5v transformer,

Can you run a SSR from just 5V? Most of the ones I have seen require at least 48V. Have you a part number for the SSR you want?