I made the mistake of parking at Boston's Prudential Center Garage the other night.
I read the sign and thought that nightly parking rates were $12 after 5 PM, but no, they use the DAILY rates at NIGHT.
You need to be validated to get the $12 rate.
Prudential Center Garage Rates
Enter after 5:00PM and exit by 3:00 AM
$12.00 flat fee with validated parking ticket.
Daily Rates
0 to 1 Hour $9.00
1 to 1.5 Hours $18.00
1.5 to 2 Hours $27.00
2 to 10 Hours $35.00
10 to 24 Hours $39.00
D'oh!
Be careful.