Thanks again for your detailed answer and I ended up going for the Robo Rodipet house in the end and I did buy a little toilet tray which I hadn't thought of before. I thought I would let Layla play in it when she is free roaming and see what it is like size wise. I rescued two robo's over the course of the last 2 weeks so if it is too small for her I will put it in with one of the other tiny ones. I did go a bit mental on my order and noticed they have also started selling an orange sand bath rather than the huge digging boxes so I am really looking forward to seeing what this is like for Jude who is a Syrian:
RodipetŪ Hamster Sand Bath
Jude has a trixie labyrinth house which I did remove one wall but couldn't get the floor of it out. I did waterproof it but I noticed when I cleaned it last night he is starting to keep food and wee in the same room which gets really smelly. I wish I had ordered a Syrian house now too.