My system was a complete custom DIY build, from room design through system configuration and tuning. It took over 14 years to reach its current state. Even though I've been a life-long audio-nut and gear-head (and computer professional) I invested tons of time learning about acoustics, testing and measuring, and trying different things. The outcome is one of the most satisfying systems I've ever heard (and I've heard quite a few six-figure custom setups), so it can be done on your own. You just need to invest the time to learn and do.
Now, if you want to get there quicker with more assurances of success, then yes, do hire a professional to help design the room. You will find that even if you pay big bucks, that it will be way cheaper in the long run, as you wont waste time and energy swapping out gear looking for a better sound.
Now, if you want to get there quicker with more assurances of success, then yes, do hire a professional to help design the room. You will find that even if you pay big bucks, that it will be way cheaper in the long run, as you wont waste time and energy swapping out gear looking for a better sound.