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The labor time to replace the hose is no more than 1/2 . you'd save yourself lots of headache if you let the garage repair it. the coolant system has to be bled once the hose is replaced. if you tear into this yourself and you ran into a problem it's cost you more money to fix.
there are tow radator hoses, they both get replaced fromt the top. the average labor hour
yes the heater hoses that run to the heater core there are two in and out. pressure and return, both get replaced from the top.
unfortunately there is a step by step process for this. the air filter housing needs to be removed. below is a picture of the hoses.