Hana

Hi all, I would like some advice regarding applying for a partner visa. I have known my partner for 3 years and we will of been together for 20 months and defacto for 3 months at time of application.we have registered our relationship to register the 12 month requirement. main issue is we don't have a joint lease, my partner icon the lease with his 2 friends, who we live with. But we do have some bills and official mail to our address. We have a joint bank account we use for groceries and rent. We plan to include evidence from the last 20 months in our application to prove it is genuine. Will the 3 months defacto evidence be enough? Do people recommended using a agent since are financial/housing evidence is limited? Or do we go it alone? Thanks hana