what is a resonable price to repair a intake manifold gasket with parts & labor? on 2003 Chevrolet Venture

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my husband just paid 500 to get a intake manifold gasket repaired plus labor and I don't think that was a fair price when they don't even cost over $40, am I wrong?
(1) Answer
Raise the hood and take a look, see all that stuff on top of the engine, in the back also? Well it has to be removed plum down to the motor, which you can not see by the way, so the cost is not just for the parts it is for all that labor it takes to remove, clean everything and reassemble, as should have been explained by repair facility! Not a bad price at all i think for INTAKE gaskets replacement!