Thanks for the suggestion.
I will fly UA. Once on Saturday 8/27, and another time on Saturday 9/17.
I don't mind sleeping straight on hard floor - so if terminal C or D area is not closed to public, that might be a good spot. Do you know if they are closed?
And if my flight is on next morning, do the TSA allow me to enter the air-side the night before?
I'll also check priceline, if it is $35 - that'd be great