Placing the antenna in the attic will start you at some disadvantage. How sever will depend on the materials used in the roof construction.
If you must mount in the attic (the HOA and city can not prohibit or impede you...
http://www.fcc.gov/guides/over-air-r...n-devices-rule), then use the largest antenna that will fit. I'd suggest the Antennacraft HBU-55 and a RCA TVPRAMP1R preamplifier at the antenna. I'd forgo the use of the amplifier in the basement and use a passive splitter instead.
Your HDHR will provide excellent signal metering functions.
http://forum.tvfool.com/showthread.php?t=820