Setting up a system in a nearly empty room, once you have studied and obtained a theoretical grasp of acoustics, is a great way to learn the science and the art. And you don't need to spend a lot of money to experiment ..... piles of boxes, wool and cotton blankets, large pieces of foam can all be used for the experimentation. Once you've figured out how to optimize to that three-dimensional image we all strive for along with natural ambiance, if the room is to be a listening room, then make the dollar committment. And you won't waste any, so you'll know exactly what you need.
Once you've got those experiences under your belt, in my experience, it is fairly easy to arrange a living room or family room so that it works acoustically. If you've moved a couple of times, you can even get to the point of visualizing the acoustics as you lay out the room patterns, and won't have to change much once you have things in place. Setting up in multiple rooms over time also has the advantage of teaching you what imperfections you can tolerate and which you can't. Ah, it's good to be an old geezer! :-)
Once you've got those experiences under your belt, in my experience, it is fairly easy to arrange a living room or family room so that it works acoustically. If you've moved a couple of times, you can even get to the point of visualizing the acoustics as you lay out the room patterns, and won't have to change much once you have things in place. Setting up in multiple rooms over time also has the advantage of teaching you what imperfections you can tolerate and which you can't. Ah, it's good to be an old geezer! :-)