aluminum boat repiar and paint

[tomo]

Hi, my name is tomo and im new to this so please bare with me. I bought a 16ft gregor aluminum boat used, and knew that it needed some help but didn't untill last week know how much! I wanted to strip the paint and repaint so i and some friends fliped the boat over. the bottom seems to have a very hard epoxy paint ! the seams which are a thicker aluminum are pitted from salt where the paint had blistered when I say pitted i mean really bad!! but befor removing the paint that was covering them the boat did not leak. this is a welded boat i need to know how to cost efectivly repair this and also can i paint over the existing paint without a problem or do i have to primer it first? I would apprisiate any help that and knowlage you can give me. thanks, tomo