can anyone make a recommendation as to where in nova to buy a bike for a 12 year old suitable for 20 mile road trips and maybe the occasional off-road trip? I'm thinking Costco to avoid paying $400 for a bike he'll outgrow in 2 years.
NO! NO! NO! NO! NO!
DO NOT UNDER ANY CIRCUMSTANCES BUY A BIKE AT COSTCO, WALMART, TARGET, or any other BIG BOX store. If he's 12 get a decent mountain bike or hybrid at a local bike shop (Spokes, Revolution) that's you can get some resell value out of when he does outgrow it. Buying it a LBS does two things for you - 1) it gives you a place to take it during the first year to get free tune-ups and minor repairs and 2) it starts a relationship that can be very beneficial for you should you decide to want additional bikes in the future.