Rent and invoices
Monthly invoices for every lease, receipts with balances, M-Pesa references and tenant statements.
Deposits
Track deposits held per lease, and settle them at move-out against arrears and damages.
Expenses and KRA
Bills, part payments, withholding tax by type and payments to KRA, with VAT kept straight.
Proper books
Double-entry ledger, bank reconciliation, trial balance, income statement and balance sheet.