It could be late fees, but if current tenants have been there for at least two years continuously, that number may not be realistic. (biggerpockets.com)
In order to achieve this, we've relied on them coming organically or by manually asking for positive reviews from current tenants a couple times of year. (biggerpockets.com)
Of course, there are ways to raise rent on current tenants without complaints. (sparkrental.mysmartmove.com)