I know some venturing to Lindos and beyond use Resorthoppa and the likes for cheaper transfers. Cheaper still at the moment as there's 10% off plus another 15% if you use the dicount code 'WOW15'.
I think the 10% is only on transfers but they've started booking airport lounges, parking, etc. and the WOW15 discount can be used on these too. Just benefitted myself so thought I'd share ;D