There is a ton of info and good ideas regarding RV-12 cargo area tie-downs on this site -- try looking under the "Modifications..." thread.
David Heal - Windsor, CA (near Santa Rosa)
EAA #23982 - EAA Technical Counselor and Flight Advisor; CFI - A&I
RV-12 E-LSA #120496 (SV w/ AP and ADS-B) - N124DH flying since March 2014 - 510+ hours (as of June 2017)!
through June 2018.