1st property purchase

Hi all
We’re looking for our 1st IP. We’ll put the 20% deposit in cash as we dont have a property or access to euity.
Regarding the 80% I’m tossing up to maybe fix half the loan and the remaining on a variable rate.
I see we can use an offset account with the loan or use a redraw facitity or a LOC (which is a higher interest rate), Which do you recommend.

If i understand it, we put the required payment into the both loans and any surplus into the Loc.
Am I right in assuming that we can use any surplus in the LOC as our deposit on our next IP
Your thoughts would be appreciated