Garage build planning...need lots of advice

Ok, noob here, but i am pretty good at building stuff. Problem is i need some advice from those who know about sound and how to make the most of it. So, here is the situation. 2 car garage with two individual doors. Looking to turn the right hand side into my man cave.

So, here are the stipulations. Need it to be somewhat temporary in case we ever sold the house, and would like to keep budget small.

Here is what i have to work with. Looking into garage from outside, it will be the right hand side. To the right is wall which has living area on other side. I have a beam running right down the middle which is supportive of the 2nd story of home. Straight ahead is wall which has storage room behind it. To the left is open to left hand garage. Walls that are up have the plywood sheeting...not sure if there is sheetrock behind yet, will be finding out this weekend. And then of course the other wall is the garage door itself.

Need advice on best thing to do with the concrete floor. I live in TX and it gets hot and humid here...wondering about concrete sweating stuff.

Other plans...advice on this is greatly appreciated also. Plan on making a wall down the center and attaching it to the top beam i mentioned and then to the ends of each far wall.

Next, trying to figure out if i should put the tv/speakers on the wall to the inside or to the garage door side. Plan on cutting the styrofoam type sheet insulation to fit inside each garage door panel.

Double layering the garage door as the stuff i think is 1/2 or 3/4 thick. Thinking this will dampen sound and provide some heat/cold relief.

For the dividing wall, 2x4 studs, putting insulation (is one type or r rating better?) and the sheetrocking it with the float/texture.

Once all thats done, i would like to build some sound attenuating panels (think thats what they are called). Is this an easy DIY project, or should they just be ordered? Seems like some fabric, insulation and frame material would be relatively cheap.

But back to my biggest concern...the floor and moisture. Suggestions especially and then the next thing is the garage door side...any other suggestions on what to do with it. I want all this stuff to be easily torn out should it ever need be. Going to try and get a sketch of it all up tomorrow.

Thanks a ton

Forgot on the floor....i can lay anything that would do the job....carpet, tile, wood floors, etc. Looking for what would work best in this situation.