Record service periods, due dates, categories, amounts and sources separately.
Control the file.
Don't guess the remedy.
Reconcile every charge to every payment, credit or security application. See gross, disputed and undisputed balances, age the unpaid ledger, model reviewed simple-interest assumptions and preserve the exact evidence behind notice and payment-plan decisions.

A balance is not yet a remedy.
Allocate cash, credits and approved security applications to specific charges.
Keep the gross ledger visible while separating entered disputed and undisputed balances.
Preserve notice, delivery, receipt, deadline, plan and adviser evidence without inventing legal conclusions.
See what is owed, what is disputed and what still needs review.
Start with a practical template. Enter the ledger first; then allocate payments, record notice evidence and administer any signed plan. Nothing is sent to a landlord, tenant or adviser.
Name the file and prove the source population.
A balance becomes useful only when the complete lease and complete ledger agree.
Keep the invoice, obligation, date and security records aligned.
Use the Rent Invoice Audit to test the original bill, Obligations to control non-monetary performance, Critical Dates for professionally reviewed reminders and Lease Security to understand deposits, guarantees and letters of credit before any proposed application.