"The room can totally wreck, or make, a system"

One last point. Many of these acoustic companies will offer to study your room and come up with 2 or 3 price options. I notice these plans all but wallpaper walls and ceiling with a great number of panels. I question this approach. Start slow and test with a few treatments and go in steps! 

@onhwy61 your post is certainly true and reasonable. My experience mirrors what you stated. I have had massively to minimally treated rooms throughout the decades. I managed to get all the systems to sound very engaging and enjoyable. Natural wool rug in front of the speakers, more nearfield listening combined with speakers that work well with aggressive toe-in minimizing the room’s impact. Getting acoustic treatments right in a given room can be difficult. One of my highly treated rooms would always sound flat and a tad dull. I learned to use more diffusion and thicker broad spectrum absorption panels to avoid that result.

Furniture combined with book cases and such can certainly help acoustics if well thought out. Some of my listening spaces were in a shared living room making the use of acoustic treatments near impossible! 🙁.

Finally, I have a good audio friend that paid one of the acoustic companies mentioned in this thread many thousands to treat his room. He ended up having them remove most of it in the end. He felt the system lost life and vibrancy. I suppose some of this can be subjective in terms of sonic result. It seems everything in audio including acoustic panel types, placement and number, is also subjective.  Nevertheless, if at all possible acoustic room treatments should be employed, but realize it takes time and effort to do it your liking and preference.