Can I use Opal card in Sydney airport train to city? It looks like it costs $19.80 one way..
If I load, $20, would I be able to use it for return fare? Well Can I exit the station with a negative balance.. with myki (melbourne) it allows to exit with a negative balance, is it same in Opal?
I am reading this- https://www.ozbargain.com.au/node/442180
is this still works?