My DD is at the Inner Harbor Rennaissance right now!
DH stayed there 2 weeks ago.
DH got it for $72/night on Priceline, DD got it for $81. I would use Priceline, and look for 4*s starting at $71 and go up from there, if necessary. Add additional locations in the city that do not HAVE 4* hotels, to ensure you stay in the Inner Harbor Area.