Here is a rough idea of how to categorise and classify your transactions:
Think of classes as things such as you, your partner, joint (stuff you own together obviously) and each individual investment property etc.
By using Classes you don't need to duplicate categories & subcategories. If you used a new unique category for each investment property you would find yourself having to repeat the same income and expense subcategories all over again. So in a nutshell the use of Classes means that just one set of categories and related subcategories can be used by as many people, properties, family trusts and other businesses all in the one file if you chose to do it that way. As Sim said earlier Classes are your best friend as they keep your structure simple and consise.
So perhaps set up the following classes:
You
Your Partner
IP1
IP2 ...
Now set up expense and income Categories called something like "Rental Expense" and "Rental Income".
Under "Rental Expenses" create subcategories such as the following shown at this ATO link .
http://www.ato.gov.au/individuals/c...002/002/005/003&mnu=1009&mfp=001/002&st=&cy=1
If you set things up this way you can use either Money or Quicken to filter your reports using Classes and Categories etc. For example come tax time it is a breeze to print out a seperate tax report for each person, business and property just by selecting the appropriate class.
When you enter your transactions in Quicken they should be in this format:
Cat:subcat/Class
Have a look at the Help in either Money or Quicken also to get some further info.
But do yourself a favour and enter a few transactions to start with in this format then spend heaps of time playing with the Report Customisation options for Classes and Categories and it will all fall into place pretty quickly.
Hope this helps.
Cheers - Gordon