Wall Ownership
While it may not be a popular restriction, if your lot abuts a perimeter wall you are responsible for the maintenance and upkeep of the wall. There are multiple deed restrictions for each phase of Bent Tree West, but they contain similar content. The following is pulled from the Estates' deed restrictions.
Deed Restriction
The original deed restrictions for the Estates can be found here.
Phase Map
The maintenance clause is also referred to the the phase maps, as seen here:
The original phase maps for the Estates can be found here.
Dallas Code Compliance
In addition, Dallas code compliance outlines the responsibility of removing graffiti falls to the homeowner.

Dallas code compliance website.
Under Dallas City Code (Section 31-38) the property owner is responsible for the removal of graffiti.In addition, 
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