I have two living rooms. One is a smaller room in the front of the house where the front door is. I have my 90 gallon and 125 gallon in there, with a small antique couch. You can see the tanks from the street as you drive by (as long as the lights are on.)
In my kitchen/dining room area (it's actually really big wish I could show everyone my floot plan) I have a 56 tall tank that's fully planted. You can also see this one from the street if the light is on, it's directly behind an opening from the front living room through to the kitchen, where the area opens up into my big living room in the back of my house. I also have a 30 gallon next to my fridge, that's a hospital/quarantine tank.
In the big living room, I have my brackish 55 long, with a planted 10 gallon next to it, and another hospital/quarantine 10 gallon and 5 gallon bucket sitting on an old aquarium hood on the other side of the living room...
My house was built on a concrete slab fortunately, but I don't have any tanks upstairs, or in any of the bedrooms down stairs. I do, however have a tank in the "herp room" that houses my 6.5 ft boa, and many other snakes and tarantulas.
Our "office" is a spare bedroom, which is really just used for storage, and the extra toilet when both me and my husband have indian food for dinner!
EDIT:: sorry for the tangent, I'm a drunk a bit.