thats about right with price, labor is expensive. even though it is kind of straight forward job, it is labor intense on some cars. plus, you get what you pay for when you don't know how to do something yourself. oh, as mentioned, six hands DO help!
that being said, the glue prices seem a little steep. Lowes carries 3M gallons for about $35-40 here. while it may not take a gallon, it will take more than 1 quart, so imo you would come out cheaper buying from lowes/home depot, possibly walmart(they used to carry it).