That`s how I have my shelf!
You have two things I wouldn`t use. The small purple house (possibly put it on top of the shelf as a little eating area?) but not as a sleeping hut as it`s too small. The food dish is too narrow, so use something like a plant pot drip tray? A ceramic one works well as they won`t tip over and the hamster can sit inside it. Poundland have garden stuff in so you might find something there as a low sided food dish.
Under the shelf, if you can get a long tissue box, turn it upside down (so the floor is open) and cut a few doors at each end or one at the front. These are spacious and cosy. My Russian dwarf spend a lot of time digging about in his and nesting. They make easy, chewable nest boxes and are light enough not to harm the hamster. The box will also help hold up the end of the shelf that isn`t supported.
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