From what I see, there's nothing too much being asked of the players.
Simply put excess items on alts, and furniture can stay out. Maybe a few decorative swords (a FEW), an Ulber rug (just the one), and a bookshelf or two. Perhaps a few beds, chairs and tables, arranged neatly and in good order, with maybe a loaf of bed and a fish for dinner set out on the table.
At least, that's how I'd decorate my GH.
Think of it like a flat you rent (for free) from the Octarchy. If you keep it IC tidy, you're not likely to get evicted. But if it's a great mess, with non-approved DIY renovations and swords in sacks left lying about, they're likely to kick you out and hand it to the guild who promises to keep the place clean.
So RP a spring clean if you have to, tear down your illegal renovations, and if your place just looks like a tidy house, then you'll be fine. Don't sweat.