Some before photos:
The sat antenna in the middle of the roof had to be moved. A stud finder located the 1x1 tubing Newmar install to hold up the 3/8 plywood before installing the EPDM(rubber) or fiberglass roof.
Location of the Newmar installed coach battery bank on my Bay Star.
Bring a tape measure and find the compartment with space to contain the battery bank and controllers, etc. Mine was just forward of the fresh water tank on the passenger side.
What 4/0 cable looks like, it was expensive but has the capacity required to handle the Magnum MS2812 surge current. I can run the microwave, and coffee pot at the same time and by glancing at the ARC-50 I can see if the inverter is about to be overloaded.
I also installed a Progressive EWS- HW50C surge suppressor post transfer switch and the remote in the panel above the entry door to be able to monitor both the 50 amp current from a power pedestal and the generator's power.
The inverter also powers the 120 volt AC heat pad under the water tank.
There are lots of places that will install a cheap system composed of the cheapest parts and designed to maximize the profit of the installer. Ask the installer for a guarantee that their work will provide to the battery bank power within 3% +/- of the panels rated capacity.
You have to study the current market to identify the best stuff for your great Newmar motorhome if you want to get the most quality for your money. I thought in 2012 that nothing was too good for my special ordered Bay Star and set about determining what I had to do to make it equal or exceed a standard Mountain Aire (which I couldn't afford and exceeded my 30' max length I wanted for boondocking). Make a spread sheet and write up your requirements and shop for an installer that will meet your requirements for work you do not want to do yourself. I surprised several who were used to customers looking for the cheapest system versus the best system currently available and willing to pay for it.