The Inlet parking lot, officially known as the Hugh T. Cropper Parking lot has 1,200 parking spaces. It costs in the summer are:
Weekday and Weekend = $2.50 per hour
0 - 30 minutes Free
31 - 40 minutes $1.50
41 - 50 minutes $2.00
51 minutes - 1 hour $2.50
Additional Time $.50 per 12 minutes
It will fill up during the day on busy summer days, especially weekends, but there are several other lots in the area.
You can get information on all of OC's public parking here:
http://ococean.com/travel-tools/parking-information There are no public changing areas or private bath houses where you can change and take a private shower in Ocean City. You are not allowed to change clothes in the public restrooms. There are public rinse off showers to wash sand and salt water off yourself at the Inlet beach, Caroline Street, and 9th Street. These showers are on the west edge of the beach.