Escrow Payment Verification Use Case
A trusted third party takes responsibility for verifying the availability of funds in advance of the closing of the sale of a good (e.g., real estate purchase).
All of the steps to close including verifying payment, title search, etc., could be on the blockchain:
Sale agreement/contract
Clearing of contingencies to sale
Certificate of ownership/title search
Good Faith Estimate for closing costs
Proof of transfer of funds from buyer and mortgage lender to an escrow account
Final closing costs (HUD-1 in the US)
Financial clearing of seller's financial obligations (if appropriate)
Proof of purchase and transfer of title