Brat dumping and Rental Agreements

I live in WA part of 8 townhouses, half are owner occupied and half are rented

We have a noisy tenant and we have issued a Notice to Comply (to tenants and owners) however part of the Notice to Comply states that they must comply with the obligations within their Lease.  The parents own the townhouse and the son is living in the place along with various room mates.  Their is no real estate agency to go to and there is no Lease is place between the parents and the son.  Is their a default/standard lease that the Strata can use?  If so where can I find it?

Thanks