There should NEVER have been one LOA drawn up for two different cities, in two different countries, on two different continents, in two different hemispheres, with two different economies, and just ONE SET OF HARD NUMBERS for housing allowance, etc. This is gross incompetence on the part of our MEC/NC, frankly. There's also no need to reinvent the wheel here ... it would have been simple to peg a Captain's HOA/COLA to, say, the DOD allowance for an O-5, and peg an F/O's HOA/COLA to the DOD allowance for an O-4 for each particular city. The DOD has already done the economic survey, the scale reflects the different in rank, earnings, station in life, reasonable (i.e., not luxurious) standard of living, etc.
This is why we need PROFESSIONAL negotiators, not pilots who think that because they can fly a mighty fine single-engine ILS, it means they're ****e-hot at whatever else they attempt. This is no time for moon-lighting, folks.