It would be very expensive to take the whole CPL course on a multi indeed. Correct me if I'm wrong but you could just do all of the CPL training on a single engine, then do the 6 hours of MEP class rating to then have one skill test for both. Or you could do all the hours on a twin, or anything in between. Perhaps it's good to have a couple more than six hrs in order to have some more practice.
I'll be doing 30 hrs of IR-SE training, then 25 hours of CPL, 6 for the MEP CR. CPL/MEP skill test. Then another 15 IR-ME hours to finish with a IR-ME skill test. Anyone here who has done similar?