✔ 最佳答案
Not everything has GST in it and you may only claim the GST if you yourself are registered for GST (ie you will be able to claim it but will also have to charge it to customers). When yo claim the GST also depends on what accounting basis you are on- ie "cash" or "non Cash"
IF you are on a cash basis then you only record in the BAS the values of items you have physically paid for and sales that have been completed and money received if on a non cash basis then you must include items that you have been billed for but also all the sales you may have billed but not yet received the money.... so that will make a big difference in relation to when you claim items.
People registered for GST you will get a BAS to fill out and in that document you work out what the actual GST was in both your expenses and sales as if there is no GST you cant claim it.
Residential rent is input taxed but I assume that you are talking about commercial rent which generally includes GST IF the owner is registered for GST if they are not registered then there is nothing to claim back. All registered vendors are required to furnish you with tax invoices and these must refer to the GST to be valid so you should fairly easily be able to work out whether the expense includes GST or not.
I reccomend that you refer to the ATO website for more info on GST, GST registration, BAS and lodgment of BAS.
http://www.ato.gov.au/businesses/content.asp?doc=/content/20724.htm