I've never liked the idea of house apps in general, I'm sorry, this made me go eww.
First, the exterior: There are absolutely no pure-black houses shaped like a u with a yellow stripe near the bottom. Look at the front of your house, or look up houses on google for inspiration, because realism is important, especially on the exterior. Add a roof, few houses are flat-topped, and if you don't at least make the roof accessible for creativity.
Second, the interior: Fill it, your house looks completely empty, all that I can see is a bed, a badly made set of TV and couches, a bookshelf, and two unrealistic counters in the kitchen. Again, looks at how much furniture is in your house, it's variety and where it's placed, your bed is probably not alone in the middle of your room. Also try to mimic that furniture as closely as you can. I guarantee that your couch is not made of boxes, nor is your tv rainbow colored. Third, add some variety to the flooring, no house has a pure black floor. Use flat prints to create a tile effect, but don't always use them. Some great flooring is: strips of 1x2 tiles using various colors of brown to create the look of hardwood and alternating black and white 2x2 tiles to create a kitchen-floory look (I think this one is generally overused). Also, don't use props, don't apologize for not using them. They definitely lower your chances of getting in to any major building clan.
