A friend of mine got a bike online (the full details relating to why aren't relevant here, the point is it arrived in a box needing some assembly).
I offered to give him a hand putting it together, with the suggestion that if he wanted to be sure of anything he could take it to the local bike shop to check it over. The total time to get everything out of the box, and get it all put together was a bit under an hour. That included mounting the front wheel, putting the pedals on, inserting the stem and tightening everything, putting the saddle on the seatpost and getting that put in, and probably a couple of other minor things.
I suspect the wheels could do with attention (maybe the hubs need some grease or similar) because on a recent ride he was pedalling down a hill while I was freewheeling and I still had to feather the brakes to avoid running into the back of him. Whether he'll want to pay the bike shop to check the hubs and correct anything is another matter.
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