Expect to pay over $200 to have your HVAC drain line flushed, yes, over $200 and it requires no parts and takes about 10 minutes. Oh yeah, they may also try to tell you that is not the real problem, that you really should replace the whole pan, it is pretty old after all, give me a break! If you have more than one problem, say a leaky faucet and an HVAC problem, that is two diagnostics at $70 a pop! Plus the repair! Move on to the next company, these guys are just too rich for my blood.