Rent and Deposit Collections

I am creating a rent and deposit tracking application. We let people pay deposits over time. Sometimes people pay late so they owe a late fee. Sometimes they don't pay in full and need to pay more next month.

Here's where I need to start:

I want to input an amount in one form and have that amount be subtracted from a running balance that is kept current in a view. Let's say someone owes me $500. I want to record that amount, the expected payment and then deduct payments from the balance. I want to track date paid, amount paid, amount due, running balance. Can I do this with Creator? And I want to do this for numerous tenants.

Any ideas and formulas you all can help me with will be mucho appreciated.