Guess you'll need to use the Final Fantasy XIV Companion App™ to more easily manage your now severely limited marketboard space! For the low, low price of $Toomuch you can even get a whole new retainer to make up for all the space stolen, er, occupied by this new system!

Seriously, it's pretty bad. About the only thing I can suggest is maybe try and get friends to help ease the burden. FC mates to put up some mannequins, if it's an FC house, or tenants if it's a private estate. Of course, that only works if you have people you trust enough to give estate access to, which not everyone does.