Back in 2011 I spent about $1500 on a nice solar system for my Arctic Fox 811, which I owned up until last September. I had 300 watts. I had the solar dealer install it because I simply didn't want to do it, that's why it cost so much.
Camping in WA state, I'm in the shade all the time when I remote camp, so solar didn't do me a whole lot of good.
I already owned a Honda EU2000i at the time, so that's what did a good percentage of my battery charging duties.
Where solar was a small benefit was to help offset the discharge of my batteries when my inverter was providing AC power to the fridge when I was traveling.
Another small benefit was to recharge after a night of dry camping when I was traveling from point A to point B and stopped in the middle of the trip. However, the amount of discharge on my batteries was pretty minimal since I was just stopping for the night, usually parking for the night not long before dark.
Over 11 years of truck camper ownership, It's very rare that I take a trip where I end up in the sun while dry camping.
In August of 2020, I bought an AF992 to replace the 811. I have no immediate plans to install solar on it, even though I do still have an inverter onboard.
I did opt to upgrade my truck to truck camper charging system by adding a Victron DC to DC Charger. I went Victron because it's small and compact, unlike the Renogy and RedArc units.
Victron installation video