How to record Security deposits received from the customers ?

How to record Security deposits received from the customers ?

Hi
We are a rental company that collects a security deposit from our customers and refunds back when they exit. Earlier we were using retainer payments to easily record and refund or use against invoices when needed. But now I need t a professional plan in order to use that feature. I am happy with the standard plan itself. Apart from the retainer invoice, I do not have use of any other features mentioned in the professional plan, so I would like to know if we can handle collecting security deposits and refunding it back or use it against invoice in some other way ?

thank you