So I have my home on my island, my main character's home. I have a second character, but I use the home as storage, and use her to get bonus items. But as for how the home is designed, I created it to be like a spa, reception area, three main rooms, a cafe of sorts on the second floor, and basement is still in the works. What you can do is do the same, see if there is a place you want to have something build, create a profile for a new character (you don't need multiple Nintendo accounts) and do what you will. If you have something in your main characters home you want stored, or want used in the 'new building' just place or drop, go into that other character's profile, grab and so on and so forth.
