hmmm I don't think you need the (0) in front of 80 after 81. that 0 is for telling them its a different area code which is not needed when the (81) from int'l is used.

to save costs I would use a public phone, in which case you do need the (0) to make it a domestic call

iirc if dialing from international, 81 for country code, then area code, without zero.