Getting longer leases with standard property management

[Dimitri Paspalaris]

I was pondering as I was driving to work that most rental leases are anywhere from 6 months to two year. Has anyone tried convincing a property manager to get a 3 or 4 year lease signed. I understand that property managers make a lot of their money when signing the lease at the beginning and between leases with the signing fees, but as investor if I could keep a tenant in the property for more time I think it would be better for me. What is yals opinion. Thanks