Surely all that is needed is a rational conversation with the tenant when he or she moves in. The conversation could go like this:
LL : As you can see, there's lots of storage space, but some of it is above normal head height. It's probably not practical to be accessing those high cupboards on a daily basis, but if you want to use them to store stuff you rarely use, you might like to borrow my stepladders/step-up stool, or provide your own. Is that OK?
T : Yes, that's fine, thanks.
or
T : Actually, I don't really need to use them anyway.
If the tenant has mobility difficulties or is frail, then you would offer to put/help put their stuff in there yourself (assuming you are able), on the understanding that you would not want to be doing that frequently.
If the cupboards are a spacious as OP makes them sound then the accessible lower half is probably enough for the average single resident of a room in an HMO anyway.
Your only other practical option if you are really worried about being sued is to fit locks to the upper cupboards and not allow them to be used. Seem a bit ridiculous though.
I have dreamed in my life, dreams that have stayed with me ever after, and changed my ideas; they have gone through and through me, like wine through water, and altered the colour of my mind. Emily Bronte
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