Macquarie has a different entry method, which is Non-Award and SIBT.
You may be interested in SIBT - Sydney Institute of Business and Technology. This school is located on Campus at Macquarie University and offers diplomas and advanced diplomas in the areas of Business, Communications etc. These diplomas and advanced diplomas lead into the 2nd of certain Macquarie University Degree programs but entry is subject to academic performance. Places at SIBT are full fee paying.
For more information, please visit
www.sibt.nsw.edu.au
For non-award:
It is a year, full fee, in which you undertake (from memory it says 2, but ive been told by people who have done it that it is in fact not restricted to 2 per semester/4 per year) studies in individual units rather than a degree/course. You enrol in the units and are treated like everybody else, only difference being you are not enrolled in a degree program. You can complete various *core* units (being the compulsory units/subjects you need to do for your degree) at this stage, unless its specific (like law for example).
The number of students with UAI's over 70 who apply has increased quite considerably over the last two years but remember that the pathway is not a competition. If you complete the requirements you can still transfer into a degree. The higher your UAI the better your chances of success. It only requires you to pass all your units, in which case by the end of it, you will be enrolled within a B Arts or a B Science for a GPA of 2.0, or a B Arts - Psych for 2.5.
It is possible to enrol concurrently to two different Universities but if you can gain entry to a Uni then you are better off studying there and then applying for a transfer to Macquarie as you can then pay for your study through the HECS scheme. Non-Award will cost you an up-front fee. The difference, however, is that to transfer from another University you will need to reapply through UAC to transfer to Macquarie and you'll need to at least pass everything in your first year at the other Uni and even then your application will be ranked against other applicants for a place. Through non-award if you pass everything then you are guaranteed a pathway into Macquarie - we do recommend the 'other Uni' option though, as if you do fail anything in non-award then your chances of moving into a degree are almost zero. Whereas if you are enrolled at another Uni, and fail something, you usually get a second chance (and in most cases a third chance) to pass the same subject again and can still get a degree. Of course if you fail anything this will also mean that you probably won't be able to transfer to Macquarie later but at least you'll still be at Uni, in a degree, that you can complete and graduate with.
The other thing to consider is that if you completely stuff up and fail the other uni course you can still come back and have a go at Non-award but if at any time you fail something in non-award then you can't then use it as a pathway to Macquarie.
If you have a UAI over 70 I think you can be fairly confident in passing either non-award or first year Uni at another Uni. If your UAI is much below 70 then take heed of my advice above in relation to the possibility of failing - getting into a Uni course is the most important thing and if you can gain direct entry then this is obviously preferable.
It would be helpful what courses you are looking at specifically.