Small RIB project cost?

[Nojjan]

I have for while (okay for a long time) been planning to build a small RIB boat. Simple and light for a 90-100hp outboard, 6-7m(20-23ft). I am wondering if anyone here has done something similar on a amateur level and what kind of costs they accumulated?

[kach22i]

I think the number one cost is doing things two or three times to get it right.

Also there are costs or consequences involved when not following plans and making changes. These are just general observations and not pacticular to your project.

My projects easily take twice as long and cost twice as much, but I work outside of the norm on purpose and expect to pay for my ignorance.