Not done Brakes but did similar a few times on agency.
Never had to put anything away as most places don’t want you messing up their store room, plus they want to check the stuff off. Plus bottom line is they don’t trust someone strange not to nick stuff.
Some stuff will be humped up stairs, but in my experience most store rooms are on ground floor - the staff don’t want to lug things up and down either. Plus there’s the risk of trips and falls so they don’t want you wandering too far.
Bottom line is they are paying you a lot more money than I get for class 1 ADR nights for a reason (even if I do plenty of overtime). It’ll be a bit of graft but there are limits to working time. Salary is good as you don’t worry about low weeks such as after Xmas.
Personally I’d go for it even if its 6 months, plus it keeps you fit.