Female marking

Question
I just recently adopted a 6yr old female silky terrier that was just recently fixed. She was a rescue that was basically used as a breeding dog and never really handled.  We take her out often and she urinates but in the house I keep her on a leash to keep her from marking in my house.  When she is on a leash she is very submissive but off the leash she is more dominate and wants to mark.  I have never had a female that wants to mark and I have no idea how to stop this.  She will go outside but if we don't leash her she will run around the house to find a place to mark. Please any help you can give would be wonderful.
Melissa

Answer
The first thing I would do is clean anywhere she has access to with an enzymatic cleaner-there may be remnant smells she is covering.  Also limit how much area in the house she has access to.  As she is trustworthy in that area, increase her room slowly.  Too much too soon can be difficult for a new dog, especially one that has not been well socialized.