Simon Sharpe executed and delivered to Ben Bates a negotiable promissory note payable to the order of Ben Bates for $500. Bates indorsed the note “Pay to Carl Cady upon his satisfactorily repairing...

Simon Sharpe executed and delivered to Ben Bates a negotiable promissory note payable to the order of Ben Bates for $500. Bates indorsed the note “Pay to Carl Cady upon his satisfactorily repairing the roof of my house, (signed) Ben Bates” and delivered it to Cady as a down payment on the contract price of the roofing job. Cady then indorsed the note and sold it to Timothy Tate for $450. What rights, if any, does Tate acquire in the promissory note?