What you don't need when your are buying a C-Dory with all of its mystique and luring qualities and your "really want it" bone in high chat, is someone to give you a treatise on using caution in boat buying. BUT...not knowing your age or situation in life, I have a few thoughts that may be useful, or downright insulting. They are however based on my middle class background and having bought and lost a LOT of money on motorized toys over the years.
1. There is nothing wrong with wanting a nice boat and the C-dorys are in fact, very nice boats.
2. Boats fall into two classes, disposables, and C-dorys. The disposables have common names, familiar to us all...bayliner being one of many. Some people call them milk-bottle boats. In any case, C-dory and a very small group of other boats are built for the maximum pleasure over the longest period of time. So, you are on the right track for a boat.
3. All boats, including C-dory, over the first year or two are never as thrilling as they seem in the beginning. The new boat buyer needs to be particularly aware of his or her ability to choose quality and long term enjoyment over immediate gratification of something powerful and painted nice and equipped for maximum escape from the humdrum of daily life. (Hmmm, kinda sounds like picking a wife or husband.) Another way to put it is that some boats are marketed to front load the pleasure to get you to put out the maximum price. The letdown comes a couple year later. You won't find that with C-dorys.
4. If you haven't bought a lot of boats over the years, consider carefully buying a well used, but well maintained C-Dory, even if it is 20 plus years old. If it has been maintained, you will be buying a nice boat for 20 or 25 grand instead of 50 to 70 grand.
How does this obvious stuff relate to your post? Even if full financing is available, it is a sucker deal over the life of the loan. And, stuff happens and that big ol' monthly payment may be a real albatross in the future. The 20% rule is a good one. My boat and other powered toy buying has always been with 50% down. That way I KNOW that I can get out from under that loan within a week or two because my boat will sell easily and at least cover the loan balance even if I have to sell it in the off season.
Consequently, in my personal financial position, that keeps me in the used boat market. That is a rich market. After all, a well built and maintained boat has a near infinite life when re-powered and re-electronic'd over the years.
So, I would always recommend that you find a boat that fits your ability to put 20 to 25% cash down, or even more if you can, and end up with payments that are relatively trivial to your own financial position.
You will be able to find C-dorys that are solid and with long life left on motors and electronics for half or a third the price of a new one. Someone else will have taken the major depreciation hit of the first year of two.
Now, if you are one of those folks who can pony up the money for a brand new boat, then god bless you. Without folks buying the new ones, then there would be fewer good used boats on the market for guys like me.
In any case, a boat is only as valuable as the amount of time you spend using it. Some boats cost their owners a thousand dollars and hour over the life of the owners owning that boat. because they use is so little. Others will own that same boat and only be paying a few bucks an hour because they put so many hours on their boat.
I hope you are or will be the latter.
So, there are my stream-of-consciousness thoughts which may or may not apply to your situation.
Oh, to comment on what you asked, I've done all of my boat and toy buying through a credit union. They seem to have more understanding and flexibility than any bank I've ever worked with.
Cheers, and happy C-Dory...ing.