I got an email about $5 parking if booked online or via app for weeknight or weekend parking at 123 Albert St Car Park.
The only matching price is the Brisbane City Council undercover parking: King George Square and Wickham Terrace but they can't be booked online and are often full. Please like/comment/share this suggestion comment on the BCC Facebook wall to support online booking and/or provide a busyness graph.
The RACQ Secure Parking codes for nearby car parks are minimum $8 now including booking fee.
Update
Now $6 but RACQ is now also $9 with codes and including booking fee.
Thanks op