I am also new to the off road nitro rc world. I recently purcahsed a fully assembled kit from ebay. I purcahsed this for $240 australian plus shipping.
The buggy is very well put together in my opinion and the opinion of my local hobby shop, they have the same model on shelf and sell it for $900 retail!
It has a .21 3.5cc SH motor that is running very nicley but I am still in the break in stage.
The kit is brand knew and came from a hobby shop in Queensland.
If you are trying to save money this might be a good avenue, just remember to pay via pay pal for security (they chase up money if there are any problems) and check the sellers history.
Hope this helps.