Went Sainburys for some whiskey and saw at the front of the store a toy sale, the Lego Catamaran was £26.25 so a quick google search told me this was the cheapest as next best is about £35 which is RRP, so happy days and if you buy it your eligible for 2 Lego collector card packs too double lego happy day.
As I say it's Instore so not sure about online but should be national.
Store found in - Crayford
Kids can recreate the thrill of boat racing with this super-cool LEGO Technic (42105) Catamaran toy that rebuilds into a Race Power Boat. For the first time ever, this LEGO Technic rebuildable catamaran-to-race boat model really floats on water! Kids can set the catamaran in the bathtub to recreate speed sailing adventures before rebuilding into a Race Power Boat. So, sailing boats enthusiasts can learn while they play - how the sails work or how the daggerboards maximise stability and how the rudder steers. With the classic 2-hull catamaran design, this model boat is a fantastic recreation of the real thing, to build, rebuild, play and display. Have fun building the exclusive racing water vehicles – inspired by real race boats. To build the Race Power Boat you’ll find extra instructions online. The catamaran toy measures over 12” (32cm) long, 8” (22cm) wide and 17” (44cm) high. Contains 404 Pieces."