Hi Letitbe.
I am a property manager and I would strongly recommend you hire a company to do the test and clean of the smoke alarms.
If you have paid someone else to ensure it is done correctly, you can be assured that if anything bad were to happen (fire) then you have a third party to shift the responsibility to.
In Queensland owners are required to "test, clean and properly document". the legislation does not stipulate what 'properly document' means but to be on the safe side, we always insist that our clients use a third party company, both to protect our agency and the client from prosecution or a civil claim.
It's also tax deductible and quite cheap really.
Hope this helps.