Parts car clarification

I have read this section of the rules a couple times, but for recoup clarification you can recoup $1000 worth of parts Off your challenge car.
 

But if you buy a parts car you could recoup 100% of you parts car? So effectively zeroing out that entirely? 
 

So buy challenge car for $2,000, sell $1,000 worth of parts.

Buy parts car for $500, use the engine and trans, sell misc parts for $500. 

you still then have $1000 to spend in the budget? 

"Up to half the total annual budget may be recouped by selling parts originally included with or attached to the Challenge car, related parts car(s), or related parts packages at the time of purchase. You may not factor gains or losses made from buying, selling or trading unrelated parts into your budget. 

You may never recoup more than a part or car’s purchase price or fair market value (whichever value you listed on your budget sheet)."

Recoup includes "related parts cars", as seen in the couple of sentences you linked.

You can recoup $1000 total. 

But in your situation above you could trade the balance of your parts car for other parts you need for your build.

Now that the event is always $2000, the wording on that really should be cleaned up. It should just say, “Up to $1000”