I don't think there is a 'typical number of hours' - it will vary on the size of aircraft, whether it's an internally run course (for an operator's own pilots) and whether simulator and/or instrument rating privileges are to be added. at an educated guess, I'd say an off the shelf course for a light twin (e.g. AS355) would be about 5 hours and a full blown course with BHL or CHC for the S-92/EC225 more like 25+ hours in the simulator and 5-10 in the aircraft. Typically, an operator would be adding the TRE authority to the candidate too, for one of its own pilots, as training captains that can't examine aren't that useful in the rotary world (more common in FW.)
Prices at the top end will approach £80,000 for a heavy type course off the shelf to a third party, probably around 10% of that for a light twin.