Help! Info needed on renting our home.

If the mortgage is in both names you need to check if the title is a joint title in both names also. Nett rental Income will then be split into half. Look into land lord insurance to cover you for lost rent, ect.
You need to find out what the council rates are it should be coming in the mail or you have next years rates notice already.
You need to find out the water rates.
You need to work out the insurance cost.
You need to work out the interest cost of your mortgage for the time the property is rented.
The property Manager can access the likely rental you will receive for your type of house. You could also look at similar houses in the area that are rented out to get an idea of the likely rent.
You may need to pro-rata all the costs to the percentage of time rented versus PPOR  use
Nett income =  Rental income – council rates – water rates – insurance – interest cost
If ownership is joint you split this nett income into two
Then if negative subtract each half from each wage income taxable income earned
Then work out the tax paid for the year and then work out with the reduced figure the tax you should have paid on each wage earner.
if you want to calculate the tax payable on your wage goto http://www.ato.gov.au and search for tax rates
the amount of tax reduced depends on how much you both earn due to marginal tax rates.

As you are changing the status of the property from PPOR to investment you need a valuation done to cover you for later if you ever sell and want to work out the capital gains tax due.

Contents insurance ideally would cover the fixed items like curtains, carpets, raised floors, fttings
Landlords insurance may cover these things you should look into  landlords insurance.
see http://www.cgu.com.au/cgu/cgu/linkAuthContent.do?contentId=%2FOurProducts%2FPersonalInsurance%2FLandlordsInsurance
for an example
 the term Liability is for Public Liability if someone gets injured on your property you could be sued.

primary place of residence

if you move back you need to get a valuation also as you could end up with capital gains tax for the future sales capital gain proceeds even though you live in it as PPOR. You have the onus to prove via records that when you moved back in your property was worth a certain amount. There is a mention of this situation occurring to a seller in the August edition of the Australian Property Investor magazine.

PPOR is a term created by the tax department in their capital gains tax legislation and is significant for getting a capital gains tax exemption for PPOR. Primary place of residence is also exempt in some states for land tax calculations .

you may see the term ' main residence' as the term PPOR has been changed by the ATO
see
http://www.ato.gov.au/individuals/content.asp?doc=/content/36883.htm