Dual subs and room size

Thank you all for your comments and insights. I do have wall treatment and bass traps in the front wall corners. I have large framed maps on the walls and tried to reduce the effects of the glass. You all have put forth a lot of info, much of which I'll have to digest. Simply, I was thinking two to provide a balanced stereo sound across the freqs. I don't do thumping overbass and didn't want to find my space overloaded by using two. In the end perhaps the conservative approach would be to start off with one and see how it sounds.

Thank you all for your discussions and info, I appreciate it. Been doing much reading since thing thread started and have learned a lot. Haven't made any decisions yet. My budget is $950 so my options are somewhat limited. Any specific recommendations would be helpful.
 Reading about nodes/anti nodes was thinking about my room. The room is 17' X 10' that opens to a 10' X 10' room directly behind my seat. My chair is right on the line that separates the two. Next to me is a 13" X 8" pillar. The reason I bring this up, I never calculated the smaller room  as part of my listening space. One of the articles that I was reading mentioned that this type of space could act in a similar fashion to bass traps, the sine waves will travel past my listening position and dissapate. Conversely it may appear that I am sitting in the middle of a large room although on that score there is nothing that I can do. Think of the room as an inverted two layer wedding cake. Does this environment change how I should approach bass. Or the size/number of subs. Again thanks.

Again I want to thank you for your advice and guidance, I have been following your leads. Last night I spent some time moving and adjusting my current ML orig model Dynamo sub. Wow what difference. Will continue to lock it and conduct measurements. Will be ordering one sub with a thought to two after I lock that one in. Very interesting process. Dave