1. The BD is not the same type of bike that the OP has expressed interest in.
2. BD should be the last resort for complete noobs. Once someone attains a basic knowledge of their own personal geometry needs and basic wrenching skills, then BD may be a good choice.

@OP- I tried in vain to find the Service menu from the local Trek shop near me. But to answer your question- it could get pricey in a hurry in a worst case scenario. You might see if you can arrange to either meet the seller at an LBS or take it to an LBS for a quick once over. Most shops worth their salt will do a quick visual inspection and provide an estimate for repairs for free.