Supermouse3,
The Eurocontrol ADS-B mandate is on their web site, it is very similar to the FAA mandate, potentially actually less restrictive.
The Australian mandate is far more restrictive than either, for absolutely no good reason.
You will not find any serious airline people that will tell you that ADS-B is saving them any money. The last big improvement was RVSM, that had minimal (compared to ADS-B) compliance costs, and the savings of cruising closer to optimum more of the time has been measurable.
ADS-B is just the opposite, very high compliance costs for no measurable savings.
It will be interesting to see what happens in US. The US airlines are way behind any feasible schedule to have ADS-B fitted to all the fleets by the "mandate" date, they are betting that FAA will bend to pressure.
The American airlines objections are very simple, nobody has been able to show a return for a huge capital expenditure, and unlike here, nobody in US is dishonestly claiming a spurious "safety" benefit from ADS-B.
Tootle pip!!
PS: The terrible cost of refitting Dick's CJ-3 is actually at the lower end of costs to retrofit ADS-B to any "glass cockpit" aircraft built in the last 30 or so years, that didn't roll out of the factory so fitted.
It is a reasonable statement to make to say some VH- A320 have been retired early rather than fit ADS-B.