Third-Party
Got this from email. I think it is not bad compared to the cheapest in-the-airport parking (international terminal park long) @ $28.5 a day or $85.5 for 5 days if you book online.
http://bne.com.au/to-from-airport/brisbane-airport-parking
The usual rate for Alpha Airport Parking
http://www.alphaairportparking.com.au/rates.php
1 day $22
2 days $36
3 days $50
4 days $67
5 days $75
- For just $45, receive five days’ worth of undercover parking at Brisbane Airport from Alpha Airport Parking
- The five days of parking can be used consecutively or on up to five separate occasions
The Fine Print
Vouchers can be redeemed seven days a week until 13 May. Bookings are essential and subject to availability. Please quote 'Travelzoo' and your voucher number at time of booking. Book by: 30 April.
Blackout dates: 30 March to 23 April. Maximum three vouchers per customer. Maximum 10 consecutive days. Any additional days must be paid at the full rate. This offer is not refundable. No cash value or cash back. Voucher must be presented on arrival.
Good price particularly if you use it for multiple short stays.
For some apples vs apples comparisons, Alpha's normal rates are not as good as Brisbane airport parking (bap.com.au), which I've used a few times. BAP rates in turn are not as good as those from gatewayairportparking.com.au, but they're closer to the airport and do price matching.