some garages can pressurise the system and test for leaks,
some can analyse the water for noxious gasses, I;e inpending gasket failure.
others just hit and hope, water could vapourise as steam, if boiling up yes,
is cooling fan working,
could be leaky rad leaky heater matrix, pinhole in a water pipe thermostat housing rubber ring letting go, my guess its a zetec that's why I say rubber ring, loose hose clip,, what car would help , water pump gasket or failing pump seal ,
cream under oil cap as per 1-PD would indicate water in oil or dipstick tube or in breather pipes