best month to renew a lease?

[Kyle Eckert]

We have inherited 2 tenants with the property we are closing on today.  I top unit just extended their lease for 6 months, the bottom unit needs a new lease and is currently month to month.  I hope to get their leases aligned so they renew at the same time.  When do you find is the best time of the year to renew a lease?  

I would guess it is May-June as college kids are graduating college and need a place to live.  My wife thinks it would be better in July-Aug to possibly sign Washington University students.