for Tiapan 4.9 go to http://www.ahpc.com.au .. they can help with tiapan hull plans.. This is a tortured ply build.. Brett Goodall does visit this page so he may contact you.. Wouters F16 is a modified tiapan. lots of tips in building ply Tiapans around.

The tortured ply boat "Blade" plans ask Phil Brander on here.. He may have his "stitch and glue ply " Razor available.. He is very helpful and may modify plans to help you.. His idea of a enjoyable day is arms deep in wood shavings building some boat or other..

Dollar value.. depends on where you live.. what method you use and your skill..
another alternative is design your own hulls
finally you have a number of choices in full or part buys..

best of luck..