I've had that happen before. When it does, I have always just gone immediately to the next available size and driven to the exit. Politely explained it to the exit guard...never a problem.

I wouldn't try to snag a Maxima , but seriously...even if there are no green cones anywhere, it's just a sparse National lot with an empty Compact aisle, just jump in a midsize and you will not have a problem or get charged for the upgrade.

When ES is empty, I've taken a Premium and explained it to the guard. Again...it's one of those judgment calls and at a location where the premiums are a normal sight on the ES. I get the sense that as long as they know you aren't trying to snag something they'd never ordinarily put on the ES you won't encounter any difficulties. (For EA, I would probably look at the full-size aisle.)