Client was advised by third party remediation contractor that growth was present in both system air handlers. Performed system inspection and recommended installation of ultraviolet sterilizers as well as duct cleaning service. Advised client of system age and likelihood of replacement over next several years. Discussed possibility of duct cleaning and ultraviolet sanitization provided free of charge with preemptive system replacement. After discussing options further, client chose to proceed with installation of basic ultraviolet systems in both AHU. Client has scheduling conflict and I am unable to complete work today, will need to return Saturday or Tuesday to install ultraviolet systems. Deposit of $500 collected, balance of $1000 due on installation.