Many tenants choose the security deposit waiver option and pay a monthly fee instead. If you do, this article talks about how to convert to a traditional security deposit if you would like.
Once you have selected the security deposit waiver option when you request your original lease, you are locked in to paying the waiver fee for at least the move-in month. However, at any point after that, you are able to convert from the waiver option to a traditional security deposit. All you have to do is fill out this form requesting the conversion, sign an amendment to your Lease Agreement, and then you have to pay the full security deposit amount to be held in escrow. The security deposit waiver fee remains in place until you have completed all three of those items. Once a new month has begun before any of those three have been completed, then you will have to pay the waiver fee for that month.
Please note that even after converting to a traditional security deposit, the waiver fees that you have paid up until that point are non-refundable. Your security deposit that you pay will be refundable, assuming you don't damage the property or leave owing any money on move-out following the completion of your normal lease term with valid notice to vacate.