re: Looking at getting this bass boat...opinions?

If the boat hasn't been stolen, the current owner or whom ever the last owner was that had a "good" hard copy registration needs to renew it through WLF then the transfer process can be made legal. If and when you are stopped on the water by enforcement, you will be subject to fines without a proper registration. If they run the Hull-ID and find it has been stolen, they will seize it. Without proper papers I would certainly stay away!
The trailer is another matter but should also have a current registration through the dmv.
You can have all the "bills of sale" you want and they do you no good with out the registration being in your name. Bills of sale should also be notorized.