Chris J Dixon formulated on Tuesday :
I would have to store it outdoors - any suggestions for chaining
it up securely?

I have several alloy ladders to store, I fitted home made welded heavy
angle brackets bolted through from my workshop wall. The middle of the
three brackets is hinged allowing a padlock to lock them all up in one.

The back of my workshop is not over looked, so the ladders are well out
of sight of prying eyes. Smaller step ladders fit neatly out of the
way, in the roof of my hut.

I cannot comment on the actual tripod ladder, I have never used one.