Airport Fast Park @ BWI has a frequent parking program - in the past, it's been 7.00 at the West Nursery Road lot only - now, they've got a 7-day a week coupon for both the Red & Blue lots!

http://www.airportfastpark.com/main/...oreCoupon.html

Participate in their Secret Shopper Survey & get 8 points towards their Frequent Parking Program:

https://www.airportfastparkandshuttl...opperinfo.aspx

8 points = 1 Free Day
40 points = 1 Free Stay (7 Consecutive Days)