living off credit cards and putting all our wages on our loan?

yes this is a good idea and yes you will save on interest

There a differeent ways to do this.  What you mention is a loan with a redraw facility but you can also have a loan with an offset account.

Your solution depends on your current loan type and what it allows you do and for what cost. My advise is speak to your lender

however..

My preference is to have a Loan with an offset account linked to the loan account and pay all the salary into that, with most purchased paid by credit card which in turn is payed off automatically at the end of each month avoiding credit card interest but saving loan interest.  This saves you money becuase the money in the offest account is "offset" agains the mortgage and therefore you only pay interest on your loan balance minus the amount in the offset account. For example say you have 300K loan and 40k savings you therefore pay interest on $260K not $300K

I prefer the offset acount option on my home (offsetting an interest only loan) rather than using a redraw facility on a principal and interest mortgage becuase it allows more flexiblilty should I there be changes to a property structure but gives the same interest saving benifits as well as other advantages. Say for example you go interstate/overseas and want to rent your home, in the above structure you can gear the loan against the original loan amount and not the reduced amount.  it also allows a larger buffer zone if things get tight but  it allows you more buying power and leverage should you wish to buy other investment property in the future. I would however only recommend paying interest only on your home PPOR if you are diciplined savers and are infact saving the same or more than the equivelant princpal and interest repayments 

Hope this helps

She might of set up a mortgage off set account for you ( its usually set up against a P&I Loan) . I have one as long as you only use your card for your usual expenses ( your budget ) and pay your monthly bill it should be fine . It can also help you keep track of your spending . I'm only a newbie at all of this……. so i hope that helps

If you have a 100% offset account you can save interest by keeping money in this account. Each day your money is in there, the more you save. The idea is to use the credit card with an interest free period so that the money you would have used to pay for groceries etc stays in the account longer saving you interest. You then pay the credit card off in a lump sum at the end of the month before you will accrue interest. If you save interest in one month, then the next month you will be saving interest on interest, with the effect increasing over time.

But, you must be disciplined. If you forget to, or cannot, pay off the amount owing on the credit card in full, then you will be charged much higher interest.

You can also get points and bonuses with some credit cards. I use Westpac's Altitude card and get Myer gift cards with my points.

If you have a few investment properties you can save a fair bit and get heaps of points too by paying for rates, insurances etc (don't let the agents pay them on your behalf).

I've wondered myself if it would be cheeky  to then transfer the credit card balance to another bank on one of those low 18 month intersest rates of 2.9% I have seen advertised.