Write up what it needs, be honest and don't bash the other guy too much to the client (makes you look bad).

then write that it needs a full evac and recharge. Nothing wrong with writing up exactly what needs doing.

Commercial 5 ton Ducted splits, cheap customer, reinstalled old units from different location by hack job installers. Customer says units not keeping up. Leaking flairs, non-condensibles, shorted thermostat wires and more. Really wanted to let this one go but boss insists we help them out to keep the account.