Previous owner shouldn't give you the certificate
Joe,If the certificate you mentioned was issued by the U.S.DOT (Coast Guard) National Vessel Documentation Center, the previous owner should have returned it to the NVDC, not given it to you.I've pasted a link below to the NVDC. You didn't say in what state your boat will be primarily used, so the issue of state regs is hard to answer.Generally speaking, you must always register your boat in the state of principal use, even if it's federally documented. I've pasted below one of the FAQ's from the NVDC website:WHAT HAPPENS WHEN I SELL MY DOCUMENTED VESSEL?Return the original Certificate of Documentation to the National Vessel Documentation Center along with a brief note that you sold the vessel. Your Certificate is non-transferable and should NOT be given to the new owner. When the sale is finalized it is suggested you complete a U.S. Coast Guard Bill of Sale (CG-1340) that can be used by the new owner should he wish to document the vessel. Documentation requires that the new owner send in one signed original and one copy of the USCG Bill of Sale with an Application for Document ation (CG-1258) and fees. The buyer should also be able to use the bill of sale form as evidence of the transfer of ownership to obtain state registration and/or title if he chooses not to document the vessel with the U.S. Coast Guard. If you have an outstanding mortgage of record against your vessel, please make sure the mortgagee (the lender) completes a Satisfaction of Mortgage form and mails an original and one copy to the National Vessel Documentation Center. Your vessel cannot be removed from documentation with an outstanding mortgage. Documentation forms and fee schedules are available for downloading at this web site.