Can't use 12V because some 240V involved, and visa versa. Ah hell! This'll do. One of the mods can move it if I've got it wrong. Please?
Terry,
I've been tossing around possibilities for the storage of batteries, regulators, inverter(s) your BMS, DC/DC Charger, 240V Charger etc etc. bearing in mind, space and accessibility.
Here's what I have going through my mind. May I have an opinion on which is the best track to take please?
Not just Terry by the way.
Anyone with an opinion, please chime in. In my limited time here I've found there are several very knowledgeable people here. I'd love to hear everyone's thought.
Here goes.
I've found a Caravan Access Door #4 566 x 631mm internal measurements.
Seems the best one to suit the space so far.
This is 12 x 100AH Winston cells to scale for a total of 300AH.
I think this will be an overkill.....but!
It also leaves bugger all room for anything else.

This is 200AH which is probably more reasonable.
(Usual LED lights, chargers etc plus 240V Bar fridge, small TV, Fetch box maybe, single element induction cooker, electric blanket and Inverter microwave. I've got room for 600W of solar on the roof with the pack rack of the tow vehicle so far unused.)
This one gives you two surfaces to mount ancillaries on.
Now, both these options mean the cabling from the inverter and everything else remains intact and only the feeds must stretch as the unit slides out.

Or, last option, with any AH of cells, only the cells slide out, and all of the ancillaries remain static and accessible from inside via a lift up top.

Consider these as 'mud maps' or 'concept' drawing only. Although the measurements shown are probably +/- 10 mm
Please just point me to the right path to go down.
Thank you
Jim