90 days only mate . Can enter on a 30 then ( but i'd do a 60 day ) do a visa run for an extra 30 , then would have to do a border run for another 30 . But entering with a 60 day visa means you can do a visa run for an extra 30 ( making a total of 90 days ) and then wouldn't have to do a border run .
you say you want to stay for 6 months but thats not supposed to be allowed . So to do more never mind what anybody says is a risk . I'm going 10th december for 90 days , got a 60 day before i travel and will do a visa run for a extra 30 when there . Saves leaving the country .