With there having been significant changes to residential property returns over the last few years, many landlords aren't getting the return on their investment property that they should be.
Too often, some property managers take the 'easy option' and simply leave the rent the same or only increase it by a small amount in order to prevent upsetting the tenants. They seem to forget who is paying their fees... You the Landlord, and that they should be working to achieve you the best return on your asset!
It's important to obtain an independent opinion of your property's current market rental to make sure you are getting the best return possible.