This might help: Measuring Space - How Much Room Do You Really Need? by Pamela Cole Harris When planning your home décor, it is vitally important to understand your space needs. Do you have enough room to open any doors? Can you walk from one side of the room to the other without climbing over the furniture? Here are some rules to keep in mind when you plan your room update: 1. Living Room - Keep in mind that for good conversational and traffic flow, keep at least 4-10 feet between sofa and chairs. Place your coffee table between 14-18 inches from the sofa (although I would only use 18 inches if you have lonnnnng arms!). 2. Family Room - To the above rules about sofa and chair placement, add the viewing area needed for a television. To view a 30 inch TV screen, the sofa or chair should be at least 90 inches away (but not so far that you have to change your glasses prescription to view!). To create an easy flow in any room, there should be traffic lanes which are at least three feet wide. 3. Dining Room - A seated adult at a round or square table usually occupies a depth of about 20 inches with at least 12-16 inches more to pull back a chair. Rectangular tables need at least 24 inches per person and about 32-36 inches clearance between table and walls. On the serving side, the table to wall distance should be at least 44 inches. 4. Bedroom - For maximum comfort, the distance from the bed to the wall should be at least 24 inches. To allow any door to open easily, there should be 36 inches between the bed and the door. Knowing how much space you really need in a room can make planning your space much easier. Be sure to measure your room height and length, the size of windows and check to see of your room is "true" or square before you place your furniture. Doing so will help avert a potential disaster like buying a king-size bed for a queen-size room! This content provided by Home and Garden Makeover

My space is somewhat limited, but I also have a table behind the sofa, which pushes things forward a little. Our coffee table is a large rectangle and it's 20 inches on the long side and 17 inches on the short side between the table and the furniture. I don't think there's a dictated distance except there needs to be enough room to walk through and not so far that it's difficult to reach for a glass or cup on the table. 18 inches seems about right to me.

If it's a quality piece of furniture there should be a clear coat sealing the iron completely, even on the bottom, so it 'should not' discolor a rug. If there's even a small flaw in the sealing and moisture gets in, iron will rust. However it's going to be very heavy and it will leave indentations in any carpet, even a thin one. If you never move it that may not be an issue. I found it on another site and weight is not given. https://www.matthewizzohome.com/collections/coffee-tables/products/brownstone-furniture-jasper-nesting-coffee-table

Sorry I enclosed wrong photo of one of the rooms see enclosed