Anyone selling you something, 'has a dog in the fight'. You know better than I how to root for your 'dog'. FWIW, I'm an unpaid volunteer here. I don't get paid in any way if you follow my advise or not. (Wait, I own some mutual funds, so maybe I own some shares of the companies that make antennas... I've never read the prospectus thoroughly enough to know though).
Regardless of which antenna you select, it will need to be able to aim toward the south. Significant obstructions such as nearby buildings, trees and such will limit the ability of the antenna to 'see' enough signal.
If you are limited to installing on a wall or railing, the RCA ANT-751 is a compact antenna suited to this limitation. Paired with a 'J-pole' this fits well with your original request for ease of installation.
http://www.amazon.com/gp/offer-listi...&condition=new
http://www.amazon.com/Winegard-DS-20.../ref=pd_cp_e_1
As I mentioned previously, a roof mounted antenna system would be preferred. It would have a less obstructed view, delivering a higher quality signal and likely more total channels to the TV(s).
If I lived in this condominium, I'd ask for approval to mount an eave bracket and mast at the roof peak on one end or the other of the building. This would not put a hole in the roof. On that mast, I would mount an Antennas Direct DB4e and Antennacraft Y5713. I would offer to share the signal with any neighbor willing to provide their own cable and related hardware. That would mean that I would also be willing to install, operate (provide power to) and maintain a Channel Master distribution amplifier with ports for neighbors to connect to. By my way of thinking, a few months of cable bills would cost this much, after which I would be ahead even if I donated the antenna system to the condo HOA and paid a few cents a month to power the amplifier (which uses less electricity than a twisty type CFL bulb).
http://www.amazon.com/Winegard-SW-00...rds=eave+mount
http://www.channelmaster.com/Antenna..._1810_s/87.htm
http://www.amazon.com/Antennas-Direc...&keywords=db4e
http://www.antennacraft.net/Antennas/AntennasVHF.html
http://www.amazon.com/PCT-Internatio...eywords=CM3418
With an unobstructed view, the ANT-751 can be expected to receive most of the green and yellow highlighted signals listed in this report,
http://www.tvfool.com/?option=com_wr...99006b17f77a2c as well as some of those highlighted in red.
The roof mounted system would offer greater reliability due to the clear view and higher performance of the specified antennas.