Hi Jake;
Interesting question about the "other half' of boat storage.
I may not be in your travel path, but besides any cost comparison, there are some subtle differences you may want to think about in addition to what already has been noted.
Sea Angel has been in a Dry Storage facility since we commissioned her in September 2004. The crew at Marina Shores treat my CD25 as if it were their own, after all you just don't want them to drop one of our babies. Unfortunately that did happen at a facility near us and it's one of the reasons I choose this one.
It is first class and there is a very short distance from the storage rack to the water. The crew moves the boats without haste so it does not 'bounce around or swing about in the air'.
You will most likely find all the facilities will require a certification of your insurance in case of damage; as an example - a fire. Ask if you have to use 'their maintenance crew' for any work you feel you can not perform. If so, what are they certified and insured for. What kind and where can any maintenance be done.
Observe the facility crews working during a weekend, if possible. How do they work as a team, do they have any nautical knowledge with boat handling at the piers (knots, fenders, use of cleats, etc.) and how do they conduct themselves.
These may seem like simple things, but what and how you and your "investment" are treated will go a long way to enhancing your day on the water.
Please don't overlook how well the facility presents itself besides its structure: with its grounds, parking, rest rooms, ramps, fork lift conditions, how they handle oil or other stuff that may stain your boat while within the barn(walk through it for telltales), docks and work racks; just to mention a few more 'small things'.
OK, I got a little carried away but I hope it helped.
Art