As much as people worry about maryland. Keep the guns unloaded and in a case, and you will have no issues. You can even stay over night, or two. Your not moving to the state, your not staying here its fine. Heck you can even vacation here for a week or two with guns, just avoid having the no no guns ( aw's ).
There is nothing in maryland laws saying you cant have a gun with you unloaded ( and cased ) and not on your body ( does not mean going to the store, means going from legal place to legal place )
. Now this is not saying the people like the maryland transit police ( the biggest dick dept ) wont try to give you a hard time if they find out you have a gun in the car, but if its unloaded they cant do shit.