Solar needed?

Don’t leave Lifepo4 batteries at 100% or even worse don’t keep them on a maintainer. These ain’t boomer/gen x batt trys….

Actually, I had put together a 200 watt system from individual parts for well under $300. This included everythinkg down to screews to attach the z brackets. I have never installed solar but I have watched enough you tube and read articles to believe that I coud do it myself.

The only problem I have is the location of the controller.Since I have not moved my battery inside,I was thinking about putting the controller inside the basement pass thru.Do do this I would have to devise some sort of guard for the controller and components for protection when getting stuff the pass thru.The pass thru does not go all the way thru as the water heater is located on the driver  side of the trailer. This would give me wire runs of about 10 feet to the controller and maybe 5 feet to the battery.

I would say it depends.  a 200 watt panel is a nice size to keep that battery charged and to doube for the ocasional overnight stop when traveling.  but it comes down to 1 thing, can you install it yourself, or do you have a buddy who likes beer and knows how to do it.  that keeps it dirt cheep.  

for example Bourgerv has the panels I just installed for 159.99 US right now

https://www.bougerv.com/products/topcon-16bb-200-watt-solar-panel

and a solar controler

https://www.bougerv.com/products/sunflow-30a-mppt-solar-charge-controller

so for 230ish plus about 30 bucks for wires and such you have the system done.  say under 300 when you add the mounts and sealant. that system would be capable of replacing around 60AH a day, if I am guessing.  

if you can't do it or don't know a buddy you can bribe with beer/bbq then a mobile rv  rapair guy should be able to do it in 3 hours or less, so depending what they charge ...  

I have a 2018 Catalinia Trail Blazer 26TH. I am currently using a 100amp lifepo4 battery witha monitor and shunt. The unit was never pre-wired for solar  nor did it have a battery shut off but does now.

You didn't say what kind of Rv you have, how many batteries or what kind. Most new Rvs come with 100W solar panel (if not more) and a solar controller to keep the batteries charged in storage. Rvs in the past 20 years already have a battery cutoff switch which will also help with parasitic drains. All you really need is a 100w set up and a controller to float charge. If you have a motorhome you can also wire it to the chassis battery, but you may need a smart controller in case the batteries are different. A travel trailer with 1 battery is super simple. 

I have a 100 amp hour lifepo4 battery. I replaced 2 6 volt golf cart batteries when they went bad to save weight.

Lithium, yes. Lead acid, no. 

A cutoff switch at the battery will keep the battery charged while in storage and only cost about $20.

25 to 30 solar watts is enough to maintain lead acid batteries. Not sure any solar is needed for Lithium batteries.