i think he ment you can still purify in to 25l containers, then transfer into van tank.
i dont have anywhere to set my RO up so i carry it out to the van and put the hoses through a gap in the door, then purrify into my tank.
last winter i managed to get the water pipes under my garage door and purrified into 25l containers and the carried them out to the van.
i think i will do the same this winter but more 25l containers and maybe a transfer pump to move the water for me.