A 40-inch TV is on the small side for most living rooms. Televisions of this size are best suited to smaller spaces like bedrooms. If the seating area in your living room stands between 3 feet and 6 feet from the TV, then a 4K 40-inch TV can get the job done. However, a living room that allows for more than 6 feet of space between the seating area and the TV can easily accommodate a much larger 85-inch TV if you have sufficient wall space and room in your budget.