12m catamaran costs

[Richard & Diane]

Hello

Want to build a 12m alloy catamaran can anyone give advice on the sale price after completion. Will this be a wise investment.
To be designed by marine architect from a proven design
Vessell will be used for semi liveaboard with ocean going capabilities
Will have max cabin space available
Twin 80HP shaft desiel shaft drives
Hulls will be semi displacement
Look of boat will be classic style with no fly bridge
Have 30 yrs fabrication experience but this will be first boat project
We have owned a 34 ft steel cruiser for 3 yrs
Have own workshop space avalailble to build
Any help will be appreciated