This was my first attempt at house building when Sims 4 was just released. I've been meaning to share it earlier, but I forgot. If you have a copy of The Sims 4 Creator's Guide, there is an art there on which I based this house on (under Neighborhoods).
In all the houses I've built, I have to say that this one is the most comfortable to live in. I'll want to use it someday on a new Sims story.
Master's Bedroom with dressing area and attached bathroom.
I use this place as a gym/hobby room. There's also a toilet nearby. The extra bathroom was placed as I dont have any other idea what to put there.
I'm not sure if the copy of this house on the gallery has the sports equipment and TV on it already. But then, it is up to you to add them or not.
Recreation Room. I purposely didn't add too much in this room except for the piano and the lights, as I want to leave it for future items from expansion packs and/or party options that aren't really necessary to have around everyday except on special occasions.
Dining Room
Receiving Area and Bar
I placed a TV on the wall so my Sims can watch sports while they have a drink...so like real life.
First Floor General Layout
One of the vacation houses from World Adventures planted the idea for this layout.
Children's Rooms with Bathroom
Library
Bird's Eyeview of Di Lusso and front gate