A small scale RV system will include many different components mounted into a compartment in the RV or trailer. It will be specific to the install, and parts can be upgraded or replaced as necessary.
A typical system may include 4-6 100Ah batteries, and have panels mounted on the roof as well as portable, ground-mounted.
The system would be able to be charged from the sun, generator, shore-power, vehicle alternator and any combination of these sources.
Custom-built systems can be DIY or professionally installed, and can have all the bells and whistles to monitor every aspect of your system worldwide, or simply power your on-the-road needs.