I paid over $3000 to get a new ac condenser put in my 99 GS 400 (75K mi). Three weeks later I have a leak under the driver's feet coming from the bottom of the car. Service tells me that there is a tiny leak in the heater core that is not related to the recent installation of the new ac - that it is pure coincidence. I am very suspect that while service was working in the local, they nicked my heater core. Is it coicidence, or carelessness by service? How much should replacing a new heater core cost? I live in South Florida - I can live without heat and just use my seat warmers. Seeking advice.