If I want to use household appliances in the motorhome, what do I need to consider?

In the category The living area of the van

First of all, you should make sure that you are connected to 220 Volts from the outside or can use 220 Volts through an inverter. There are light and heavier inverters. With a light inverter (e.g. 375 Watt) you cannot expect that a device of 1500 Watt will get enough power.
At most camp sites, the available power is limited; in many cases you can take 4 or 6 amps. That corresponds to a power consumption of approximately 900 to 1400 Watts.