Structure for First PPOR

I have a couple of friends who are looking at buying their first home soon around 500k buy the land and then approach a builder,

So I was thinking that the best way to do it would be to go Interest only and have an offset account against the loan, would this be correct? and what are the advantages of doing this?

I would like to show them the link to this thread as to how they should structure it.

I did do a search for an old thread but couldnt find one for FHB?