SUMMER10
Coupon Code valid for eligible hotel bookings made on Expedia.co.nz or the Expedia app between 00:01 NZDT 22 January 2016 and 23:59 NZDT 24 January 2016. Valid for travel between 22 January 2016 and 30 June 2016.
T&Cs mention that you must pay at time of booking to receive the discount. Fortunately this doesn't appear to take away your free cancellation if the hotel offers it
ie West Plaza Wellington - Twin Room - 25/1 to 26/1
Expedia with code: $135
Trivago search: $150 via Hotels.com