Do you have to drop off the car before they close when returning it or can you return it at anytime on the return day?

They have a Dropbox for after hour returns

They have a drop box for the keys!

They will charge you for an extra day if it's not there by closing time or at least that's what they told me.

I got a free day! Should have returned Sat afternoon but due to office being closed i returned it Sun afternoon, used the dropbox and nobody was any wiser.