TD5 roof box/cage

I am of on my hols to Wales in August with the wife and 3 kids. I have been thinking of a roof box or cage I can put the contents of my wifes wardrobe in rather than drag my trailer around being a pain in the bum!!
What is suitable and what do you all recommend? I like the idea of a cage that I can ratchet it all to, but open to suggestions, thanks.

look on ebay for a good size roofbox, a lot of people only use em once then sell em,
my brother swears by his, but it's on a touran, not quite as tall as a disco.
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