The fact that one is locating in Porter Ranch and one is in Granada Hills, the one in Porter Ranch will tend to command a higher price because one community is newer and expanding and the other is established with fewer expansion plans for the community.
If you are a buyer, it is better to focus on the "features" that you want in a home then compare those features with similar properties in the "same" community. This is called a Comparable Market Analysis (CMA) and you could ask a Realtor to provide a current CMA for you.
You can send me the details of your subject townhome and I'll prepare a CMA each for Porter Ranch and Granada Hills for you.
Phone: (888) 525-0125
National Featured Realtor and Consultant, Texas Mortgage Loan Officer, Credit Repair Lecturer
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As the seller, a real estate professional will be able to provide you with the information necessary to arrive at an accurate selling price based on your home's criteria not one located a distance away in a different community.
Contact an agent for their support.