Here's a free opinion: one of the best accessories for a C-Dory is a trailer. It opens up your cruising area from around Puget Sound to any coastal water, some spectacular lakes, and historic rivers.
Since you are new to boating, you may have thoughts in mind on how you will use the boat. After some time with it, you may find that your use considerations change.
As has been mentioned here, a trailer is good to have for getting service done. Or, you may find that you want to learn how to service your boat - oil changes, spark plug changes, and other maintenance is not tough to do (or learn), but paying $120/hr for service is a good incentive to learn.
With a small boat like a 16, you may find that winter conditions are not to your liking out on the water (or you may bundle up and love it), and it is a lot less expensive to pull the boat out of the water and put it in a storage lot for a couple months than to keep it in the water.
The 16 is a great little boat and would be towable by most mid-size SUVs, if you decide to boat camp in some incredible places, like Lake Powell, Lake Tahoe, Flaming Gorge, Yellowstone Lake, Jackson Lake in the Tetons... yeah, I could go on and on.
It will be more expensive to buy another trailer than what you will get for a used one, if you decide to expand your horizons. I completely understand the thought of "a boat in the water will get more use than one on a trailer or in storage"... we recently moved from Texas, where we had a home on the Gulf Coast on a canal on an island. Our dock was steps from our door. We kept our boat in the water when we were home... but there were a lot of years where we used the boat in other locations (by towing it) more months than it was in the water at our dock. A boat isn't just a floating conveyance - it can be an "escape pod" that can take you on adventures you might not have considered.
Good luck with the decisions and congrats on getting your boat!