Yeah, I don't know about this either. Majorly annoying. I can sleep in the steward's bed, if he's not in it, but I could o that before Neloth made me a member of House Tevanni. I have no idea about which chest I can use which would be a safe container. Talvas is my Dunmer's steward so I would think I'd get whatever he had, but nope. All the bed/bedrolls in Neloth's house are still marked "owned" and I don't trust any of the chests for storage.
Hope they fix this too. Bethesda interns, I hope you're reading this.