What is the opinion of Reddit about the
South Shore Step One Ottoman Storage Bed, Queen 60-Inch, Pure Black?

Lockable armoires or steamer trunks are good. They look nice and offer different storage options. Check your local thrift or second hand stores. Then places like Ikea or Amazon might have some items that for your needs and look good.
A storage bed like this might also be an option as any straps and such could be hung down for storage. Accessible with a lot of room but not easily found unless your guests are really looking for it. https://www.amazon.com/South-Shore-Ottoman-Storage-60-Inch/dp/B00ZBA3JAW