My personal setup is an FZJ80 with upgraded Photoman Sequoia 150A alt. Stock lead acid start battery. Second battery is 180Ah DCS LiFePo4 mounted on LCP plate in the cargo area. Monitoring via Simarine and DCS Bluetooth. Currently charging via BCDC1225d which charges the LiFePo4 via alternator and solar. I have 110w roof mounted solar and 95w fold out panel to combine for 200w max potential. No shore charger. The 25 amp DC to DC with 180ah capacity may be a little slow at recharging, still playing with that, could swap to 50amp charger. 2000w inverter. The truck takes us on trips of a few days to weeks typically truck packing style (drive to new camp spot every day). I’ll also say this is also a shop truck that we use at shows/events displaying some of the work we do and products we sell, so very well could be considered overkill for most, including myself!
With the 150a upgraded alternator, I don’t get voltage drop at the start battery anymore when using a lot of power. It can keep up with charging, heater/AC, radio, other electronics and lighting on. I have some high watt things I power on the truck when I’m out on trips. Toaster (800w), rice cooker (700w), bucket water heater (1000w). Soon to experiment with induction cooking.
Yes you do need a strategy and plan for all these things. Experience helps a lot too. I’ve been using LiFePo4 in my truck for 3 years or so and thru that, monitoring how it works and such, I am confident on what I can use, how low I can go etc. My system can cover anything I throw at it in pretty much all scenarios i plan in being. I spend hours with customers planning their setups. It’s hard to put that all across the forum since every vehicle, system, environment, use and needs are different.