Upload & Sell: Off
Sent you an email with a photo of a different type of option. Shallow shadow box type of framing for walls with fabric behind it. I had considered doing something similar in black (due to black drape & pipe), but went with six 30x40's hung together off the pipe & drape. Ease of transport and able to fit in my tiny car, but perhaps I'll try something more next year.
I couldn't find the right sheer fabric in the width I wanted, but did find a couple solid blacks that I liked. I had planned on using velcro all the way across the top to attach the fabric, and then small tabs of velcro on the sides and bottom. Stapling would work, but I'm two hours out of town and was concerned about transporting them fully assembled. Plenty of configurations that could be played with. They're still large and you may not have time or room to do that, but just another idea.
This does lend towards catching attention with being able to go high. Again, the problem with the elevator though. Maybe a metal frame that's tall and can be assembled on site? Get your sign up at the top with a spotlight on it to really catch attention.
ps - are you sure they don't have a service elevator and is there any way they'd allow you a 10' space? Buying a little extra space (even at a premium) would save on a new setup.