Well you're from Scotland and I don't know the plastic bin brands in Europe, but I know a lot of Europeans use Ikea bins.
I just built two bin cages last week and they're really not difficult at all. I'm working on a more detailed tutorial, but the one I used is
this one. It is the easiest method and difficult to mess up. Bin cages have the advantage of being only two large pieces and very easy to clean. And the bonus for you: no bars! Just make sure your bin has a large enough floor space (others could help you with this) and is tall enough to fit a proper sized wheel comfortably. Obviously, longer is better than taller, but if you can't fit a big enough wheel that's not true. ;p
The hardest part of the project is cutting out the windows on the bin lid. I had to cut through mine with a utility knife, but a heated knife or a saw would work better. But it's fine if you only have the knife.
(Just be careful not to nick yourself... I did once on the first bin ; __
(oh and for a frame of reference, I'm fairly crafty but by no means an expert, and I've only a little experience with power tools. I still thought the bins were easy and fun to make!)
Some pics of the bin cages I made:
Note the water bottle on the right.
Deep enough to fit a 12" wheel but also still has the minimum size requirements for a Syrian.
First bin I made. This is the one I use (the other I gave to a friend). I had to special order an 11" wodent wheel to fit (the 12" comfort wheel wouldn't), but otherwise I'm glad I got the one with more floorspace. (The wheel in this pic is only 8.5")
My current set-up.
Don't be worried if the project looks hard - it's really not!