Closed on fourplex, inherited tenants

[Liam M.]

This is my first real estate purchase and I have so many questions. I recently bought a fourplex with all units rented and got the lease info after closing. I should have required to view the leases beforehand but nonetheless I am here. 

3 of the 4 units have expired leases, should I contact a PM to get them on leases? Can leases have a month to month agreement? I would be fine with M2M as long as I get a 30 day notice before they decide to move. I have set up a Cozy account for the time being to collect rent, but I feel that I am risking too much by not having a lease in place.

Does anyone have suggestions for online only lease agreements that make the process much easier? Like something where the tenant can E-sign and be done with it.Thank you