Below are some reference numbers and websites that you might need to transfer your services and hook up new services!
Baltimore City Public Works- Water is automatically transferred when the deed is recorded, takes about 45 days. If you have any questions call 410-396-5398
http://www.baltimorecountymd.gov/Contact_Us/telephone/letterw.html Baltimore County Public Works- Baltimore County water hook up 410-887-3363
http://www.harfordcountymd.gov/dpw/ws/phone.html Harford County Public Works- Water hook up call 410-638-3300
https://moversguide.usps.com/?referral=USPS - Postal Service, you can change your address right online!
http://www.marylandmva.com/LOCATION/default.asp Also don't forget to change your address on your license. This is the link to the MVA!