Good Day Vern!!
Your boat, your call Brother.... But I would slow down just a bit. :clock
I am sorry, I do not know you or how much you have seen done on boat hulls when they are "properly prepared" to be bottom painted.
Normal practice, is to buff out or scratch up if you will the factory gel coat.... :smileo :cry :arrow:
as to give an epoxy primer (barrier) coat something to stick/bond to... :thup :smiled
followed by what ever type of bottom paint selected by the person paying for...or doing the job....and at least 2 to 4 coats of this...and when I have.... HAVE... my boats done, we toss on another 4 coats on the "high traffic" areas like the keel/centerline and water line at rest areas... and where I generally scratch the boat first...when putting it on the trailer in bad weather..
So if....IF.... the job was done properly, and either the original owner...or the owner of the hull at the time the first bottom paint job was done would know this. Track the work back to this person... and many times, it is real easy (to have) to just sand it down a bit, and apply either some of the same type bottom paint.... or one more suitable for your needs. BE CAREFULE....AND FIND OUT what is there now for sure...not all these chemicals/types work together....and you could end up with a ... bad situation.
Help me with just exactly you are attempting to gain by "starting your bottom hull finish over?"...
Byrdman