I wanted to post a followup to my first message and let everyone know the status. I've also got another question.
I got a quote for install a fan to blow in fresh air. It will go in my small bedroom...which is right above my neighbor's 'designated smoking room.' In the meantime, while home, I've been keeping a window in there open a crack with a mini fan running to blow air in. It seems to be helping quite a bit with the air that had been blowing out the intake vents when the furnace isn't running. So, thank you for that advice.
Now for my secondary question. When the furnace does run, it is still blowing out smelly air. Filtered, but smelly nonetheless. Right now I'm using a filtrete odor reduction 1" filter. It might help a little bit, but not enough, plus I'm concerned about air flow. more info here.
I want to upgrade to a better filter 4" or some type of air cleaner on my furnace, but until that's financially feasible, what's the best 1" filter you can recommend? I don't care if I have to buy through a contractor, online, whatever. The only caveat is that it must be a cardboard frame. The way my furnace is situated, I dont' have enough clearance in front and have to bend the filter slightly to get it in. (another issue to be fixed down the road.)
Any suggestions on highest merv I should use, better brands for airflow, etc? I know there are a million considerations that are normally taken into account, but generally speaking.... thoughts?