My tomato plants have permanently moved to the greenhouse some time ago. The’re now too big to be moved inside the house at night. The nights are quite chilly at the moment, though, so I’ve taken measures to prevent the temps from dropping too low.
First of all I always have a water butt inside the greenhouse. This soaks up heat during the day and radiates it at night when/if it gets colder than the water temperature. This has a great buffering effect on the temperature in my small-ish (12 m2) greenhouse. Also I light three candles on chilly nights. It is amazing how effective this is in keeping the temperatures just a few degrees higher.