G'Day Gordon
quiggles has shown mastery over the situation again!
However, ask your accountant if you are considering negotiating a reduced purchase price in lieu of rent, as that would mean there was no rent for the period and you may not be able to claim interest, rates, insurance etc as taxable deductions. Remember, we can only claim the pro rata amount of expense as we received market rent. No rent, no tax claims.
Also, there must be some 'consideration' for the 'promise' to occupy the property, it would be hard to establish a valid lease with no rental payment, plus landlord's insurance may git a bit fiddly without a rental income.
For my money, yes, the owners can apply to rent the property but make sure the property manager does all the usual checks. It is your interests they should be safeguarding, not the outgoing owners. Make sure periodic inspections are still included in the management authority.
If it all stacks up, then sure, why not? A year's worth of rent in the offset would be good, take the usual bond against damage, and settle back for the bonus of a pleasant year.
A friend of mine bought a property at auction and the vendors negotiated a twelve month lease while their new house was built. My friend is very shrewd, and went through the house at the final inspection before settlement and did the Condition Report at that time. 'Oh', she said to the Mrs Owner-about-to-become-Mrs Tenant 'Everything is in such perfect condition! This will be an easy report to do!'
'Oh, no, it's not' said Mrs Tenant 'Look, the tiles are cracked around the bath, and the kitchen sink leaks, etc'
As a result of Mrs Tenant's indiscretion / haste to defend her position as a tenant, Mrs New Owner negotiated a couple of thousand dollars off the settlement due to 'undisclosed damage' at the time of the auction.
(Mind you, Mrs Tenant had her revenge by breeding puppies inside the house during the next twelve months, not cleaning the oven when they left etc, and the two Mrsess had a lovely year sniping at each other.)
So Gordon, if the tenancy is applied for, established and managed in the usual way, it is a good idea for the owners as they can then pass over the lump sum of 13 months money (12 months rent, one month bond) at settlement and they don't have to worry about cash flow for twelve months. Only you and Mrs Gordon can decide if it is a good idea for you.
Good luck - hope you like the house
Kristine