I want to become a crab man. Can you tell me more about fishing vessel's?
You will need a fishing vessel to be a crab man
what kind will I need?
There are probably many different kinds of vessels that could be adapted to your needs.  What is your budget?
I am only getting a small $1,000,000 loan from my father. So I'll be mostly self made.
You may consider a recreational fishing boat
oh, why is that a good choice? 
An older fiberglass boat would be smaller and less expensive