1) Car History - Vin Check or Autocheck or something? - Pass car VIN# and get report
2) Buyer's credit history/ratings - Pass name/address and/or social security number and get report
1) Research and find no cost (or ultra low cost API provider)
2) Provide the API details- provider/method name/parameters etc. with complete documentation
I don't need you to be very fancy in documentation etc. it can be straight to the point. It is just for me to understand and how to use the API. I am already a technical person so know the technical terms etc. So it is very simple if you know API and the provider details. PM me before bidding if you have any questions.
If you know only about the API provider(s) not more detailed about their API, still that will help me, we can discuss that too.