how long to build a narrow boat

[winf]

help me please i am considering building the shell of a 40ft-45ft narrowboat and fitting it out or buying the shell and fitting it out myself with my son
how many hours will it take to build the shell and fit it out if working part time on it ?
how many hours will it take to buy the shell and fit it out if working part time on it?
how much would it cost to build the shell and fit it out to modern look?
how much would it cost to buy the shell then fit it out myself to a modern look?

[MikeJohns]

Canal narrow boat hulls are easier to build in steel than yachts. Lots of flat plates with simple curves. I would think the fitting out would be the long road if you want a nice result, narrow boats are very pinched for space and woodwork needs to be of a high standard.
As for cost and time you are always much better off spending the time looking for a completed bargain than building it yourself. Then you can go narrow boating rather than hiding from the family in the rusting thing in the garden!
Cost is so dependant on what you can get 2nd hand or make yourself.