Hi Omni,
I'm a Property Manager based in Thornleigh but have leased and managed properties in Epping/Eastwood for the last three years. The rental market there is still strong at the moment! We recently leased one in Marsfield that had 10+ applications after first viewing.
The standard around the area is 7.7% but you can usually negotiate to 6.6%. Just be wary of Agencies that drop below this as sometimes it can compromise the service you receive.
If you have any other questions or information on rental prices you're welcome to contact me.
Hope this helps!