I wouldn't want them to put my bicycle together. They are less than motivated to do a good job. It's not really their fault you wouldn't care about your job if it didn't pay enough for you to live.
Same as craig said!!
If it does not come assembled they are obligated to not put it together for you in case something goes wrong in the process and causes injury when ridden, because then you might sue.
If it's not already assembled they will charge you price to assemble it. But if it's already assembled from the factory there's no charge.
If it does not come assembled they do not assembly for you
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