I'm quite confused to all the contract type for Seller/Buyer risk comparison. Since it's an important topic in PMP exam. So hope any expert here can explain to me the details, list down from highest to lowest risk for Seller and Buyer.

1. Cost Plus Percentage of Costs (CPPC)

2. Cost Plus Fixed Fee (CPFF)

3. Cost Plus Incentive Fee (CPIF)

4.Cost Plus Award Fee (CPAF)

5. Time & Material Contracts (T&M)

6. Firm Fixed Price (FFP)

7. Fixed Price Incentive Fee (FPIF)