With arrival at 0700 and no checked bags you can be at the hotel as early as 0830 or so. Best bet is to go to the hotel and see what they can do. There is a chance that if your room is ready they will let you check in early, though they are technically within their rights to enforce the 1200 time and/or the room may not be ready. As noted above, most hotels will let you stash your bags while you go enjoy a stroll until check in time. BTW, such bag stashing is generally at your own risk so I would leave the carry on but not the camera or laptop.