neeed advice on budget sub for difficult room

my setup is in a spare bedroom. I am not so much looking for recommendations for subs as i have spent a few hours on the forums and sort of know what i am looking for. my budget of $200 will allow roughly one 12" (BIC f12 or Polk psw505 $190) or two 10" (Velodyne vx-11 two for $229) I started on the " if I could only spend this" road. $300 gets me Klipsch rw-12d, $400 gets me Hsu stf-2, $500 gets me svs pb1000. I am afraid that even if I up my budget this room is never going to sound good and I would just be wasting return shipping fees
I dont need wall shaking bass.Just looking to round out my system with the sub.

I have or will have soon the Denon 1712, Pioneer 2 x bs-22 and 1 x c-22 for L/R/C, and some old Yamaha satellites for rear
I would say 50% movies, 40% music (classic rock mostly,ie ac/dc, fleetwood mac etc) and 10% games

I have attached a drawing of the room.Thanks to forum member rnconync for the website www.planyourroom.com.I have one sitting position in the computer chair that is 5 feet from the tv and 5 feet from the wall behind. I have only two places for the sub. Against the wall behind the chair or against the wall in front of the printer (on top of the sub from the Logitech z5500 connected to the computer)

I think my main question is do you think I will have to go with dual subs in this room, one in each position, or do you think one sub near the printer would work (this is my preffered choice)? I am embarrased to admit that I am currently using a cheap Yamaha 8" sub near the printer, and while not good it is acceptable.

Thanks for the help

this quote i found in another thread pretty much sums it up.
I cant do the sub crawl as i literally have only two places to put the sub, and most likely i will put it near the printer. The wall behind me was not a place i really wanted to use. I figured with how packed the room is with furniture and the fact the sub would be sort of hidden behind the computer desk that the acoustics would suck. The Denon 1712 i am waiting on has Audyssey MultiEQ XT. When it arrives i will try setting up the cheap sub i have now (i actually have a second one in the closet so i can play around with the duals). If I can get one of those sounding decent than I think I may treat myself to a HSU STF-2. If it takes both than I may up my budget a little to allow for two 10" subs a little better than the Velodynes
Thanks