Caster race roller on ebay $175 free shipping
http://cgi.ebay.com/1-8-electric-bug...item20aee2c3fb
2x hard case lipos and charger from hobbypartz.com
dynam dc6 charger $34.95
2s 5000c lipo each $24.70
plus $4.99 shipping = $89.34
buy a cheap used radio
$30ish
and a used 1/8th brushless set up
$150ish
comes out to about $450
and at that price you can easily upgrade to a 2.4 radio
http://www.hobbypeople.net/gallery/751548.asp
and order a lot more batterys for long days of fun with your son.