Inverters are a source of confusion for many people new to motorhoming. Having been there not long ago myself, I offer the following as an example of how I solved the problem of powering small 230V devices when away from mains hook-up (which in our case is most of the time).
This article describes the fixed installation of a small inverter in a Hymer. Although the 150W pure Sine Wave inverter was supposed to run from a 12V socket, I experienced problems caused by voltage drop along the installed 12V cabling of the van and decided to create a direct connection to the batteries. The installation was made with all components hidden from view.