In a workflow, I was hoping to be able to increase a date property by one year, but this doesn't seem to be an available feature.
I think it would also be helpful to increase or decrease dollar amount properties by variable increments, such as prices set in the products section. As it stands, it looks like I can only increase it by a set dollar value.
At this time, I still have to manually change a few properties to ensure accurate deal information for next year's renewal.