I instruct part time at an FTO. MEIR Reval costs tend to vary considerably, depending on the individual. You can obviously revalidate every alternate year by Sim(FNPT) which will keep the cost down(it wont renew the MEP of course) but revalidating in the aircraft itself can get very expensive. Typically £150 per hour for sim, and £350 to £450 per hour for aircraft. Theres also the examiners fee on top of that which will be typically £150 to £200 for test.
Personally, I would budget £750 for a sim reval, and up to £2000 for an aircraft reval. It all depends on the individuals competency of course and how much refresher is required.