Doug101:
I'm just getting started with Arduino and plan on using for home automation. Controlling of lights, ...
You should use the RTC circuit like DS3231 in such case and NTP could be an addition.
Doug101:
I've been trying to find out how to max the number of relays I can control ans switch inputs. Anyone know?
Many..., say the number. You can use Mega if more IOs are needed or additional I/O circuits - expanders driven via the bus like e.g. PCF8574.