Treasurer for Cubs, what does this entale?

[mummatotwo]

Does anyone currently do this? Ive said I would take on the role but not too sure what commitment this would bring?

Depends a bit on how the pack organise their subs, tbh.
Some turn up with their coins each week, others have parents sign up to a standing order - so, in the case of the first, counting and banking coins each week against doing nothing.
Then some groups have complicated ways of contributing to the Group Funds (for rent, etc.) or saving towards capitation, (ie, keeping track of how many were there each week and paying 'per head' but others don't.
Some have separate 'camp funds', others don't.

It can be a very simple, straight forward income / outgoings balance sheet, but it will depend a bit on the group. I think I'd have to say you are only going to know by asking the previous treasurer, or the Group Treasurer and finding out what it's like in your pack / group, tbh.
Of course, you could always make changes to make it simpler if it currently is more complicated.