As with ocean cruises, prices vary according to the vessel's level of luxury. You might find some early-booking incentives, or lower fares for shoulder seasons, but don't expect the rampant discounting that prevails in the cruise industry. For comparison, the following, with one exception, have been priced on a cruise-only basis. Fares do not include gratuities.
Second figure is the per diem fare.
But for comparative purposes, here are sample fares for peak season Mediterranean cruises. Again, fares have been calculated on a cruise-only, per person, double occupancy basis, this time for the lowest fare for an outside double cabin. Second figure is the per diem fare.