Deposits held, applied, and refunded, with a statement that shows a tenant exactly what happened to their money.
Security, pet, key, parking, and whatever else you hold, tracked apart so each has its own balance rather than one lump.
A deposit comes in through the same cash receipt path as rent, so it is on the deposit slip with everything else.
Put a deposit against a tenant's open charges the way you would a check: pick the items, set the amounts. Nothing is spread automatically behind your back.
Refund a deposit by check, with the ledger entry and the tenant's balance moving together.
Received, applied, refunded, and still held, per deposit type, netting to what is owed to or from the tenant.
A deposit applied shows on the ledger as its own line, named for the deposit it came out of, so a tenant reading three deposits can tell which one was spent.
A portfolio-wide view of deposits held, which is the number that matters when somebody asks what is in the trust account.