jimboalee said:
"Second hand"... Easier said than done. Does your nephew want a bike THIS weekend?
Second question, "How do you rate his bicycle mechanics skills?"
Buying second hand might be buying a basket of vipers.
If there is a Decathlon near you, this is the safe bet.
I'd echo that bit of caution. I bought second hand and got a pretty good bike, although with some worn parts that I didn't know about when I got it (due to my inexperience). While I have enjoyed the "journey" of learning, replacing the worn parts as and when and getting the set up correct, if it had not been for a very helpful LBS and my Dad knowing a good deal about bikes, my steed might be languishing in my shed having done less than 100 miles.
If you don't really know one end of a bike from the other, or are not confident of your mechanical skills and don't necessarily have the appetite/time to learn, second hand
can be a bit of a minefield. For me, it's been great and I've ordered my next bike frame only and will build it up myself cool:.