Hey users, first time post :)

I'm looking for a simple way to heat and cool my basement home theater. The room is 18 x 10 x 7 so it's not huge. I built it without hvac in the plans because it wasn't in the budget at the time and the way I would have added it in the first place would have been same whether the room was done or not.

Now, I've heard of mini-split systems but I'd really like to stay away from having any unit(s) on the wall, plus I'm not sure how "quiet" they actually are, low noise floor db is important in the room.

My original thought was to have a couple of registers on the upper portion of the front wall "supplying" the air and one or two registers on the lower portion of the rear wall of the room "venting" the air. I was wondering if there were any stand-alone air exchange type units that heated as well as airconditioned and controlled humidity. I think I'm more worried about keeping the air warm in the winter vs keeping the air cooled in the summer with the basement being cool as is. Any feedback on the specific subject would be cool too.

Again, I'm trying to keep this budget and DIY wise. Any help would great :)

Portable air conditioners exist that also have a heating mode. One source is Global Industrial (http://www.globalindustrial.com/c/hvac/air-conditioning/portable). The noise may be able to be addressed by getting a ductable unit and putting the unit outside the home theatre room and ducting as needed.