Power inverter Shut off

Here is the problem i have with leaving it on all night problem 1 i was worried about it draining my batteries down and the problem 2 it is mounted right underneath my bed and the fan on the inverter i have is loud when there is no other noise. The fan is not noticeable when watching tv or moving about the trailer but it absolutely cuts through the silence we all enjoy out camping. My thoughts were to just use a household 110v light switch but as i am seeing as i search the internet, that is not such a great idea and that it should be a 50a 12v dc switch.

Also i am happy with the inverter i have and im not interested in buying a new one. Just dont like to listen to the fan at night.