Pick up the annotated/guaranteed amount.
Pick up the legal amount (if there is no annotation).
Pick up the courtesy amount if there is no legal (blank) amount on the check (AND if there is no annotation).
Reject the item if the legal amount is illegible (AND there is no annotation).
Below is the rule. This is listed in the order of importance, which means that number one should be followed first and then number two, etc.:
1. Key whats on the annotation if there is an annotated/guaranteed amount.
2. If there is no annotation/guaranteed amount, key the legal amount.
3. Key the courtesy amount if there is no legal amount and there is no annotation.
4. Reject the transaction if it does not fit into any of the three categories mentioned above.