" Always require that the security deposit be paid in full along with the rent prior to the tenant obtaining occupancy. Allowing a tenant to pay their security deposit in installments after they have gained occupancy is never a good idea for a few reasons: 1.  Any financially responsible person should be able to afford the move-in amount required for the property. If they can’t afford the security deposit, you may want to reconsider your screening criteria. 2.  It sets a bad precedent from the very beginning that you are the type of landlord who is wishy-washy and will negotiate on important matters. Don’t negotiate on important matters! "

― Brandon Turner , The Book on Managing Rental Properties: Find, Screen, and Manage Tenants With Fewer Headaches and Maximum Profits