I've been trying to find a way to edit an image of a wall that has a razor edge for the corner and change it to make it look like the corner of the wall is worn and chipped.

Does anyone have any suggestions on how to accomplish this with Photoshop?

Thanks in advance

Can you show me the image please?

Quote - Can you show me the image please?

The edges of the building are too sharp for me. I want them to look worn and uneven in order to give the building an older look.

Image

In my opinion I think your image works just fine as it is.  Also, to effectively destruct the buildings would require the building alone to be imported into PS then a lot of eraser and overlay work being applied to that part of the image in order to get somewhere like. 
In the end I think the detail of the destruct would be kinda lost in the overall scheme of things.

Maybe, someone else has some ideas of how you can achieve your objective without to much hassle?

 yeah
you'd need to bring in the buildings in as a separate layer and work on that.

i wouldn't use the eraser tool, i'd use the masking tool cause it's non-destructive and you can change your mind if you want (can't do that if you've eliminated the pixel information).

look at old buildings to see how the decay looks like. it shouldn't be too difficult to replicate.

:)
retrocity

Quote -  yeah
you'd need to bring in the buildings in as a separate layer and work on that.

i wouldn't use the eraser tool, i'd use the masking tool cause it's non-destructive and you can change your mind if you want (can't do that if you've eliminated the pixel information).

look at old buildings to see how the decay looks like. it shouldn't be too difficult to replicate.

:)
retrocity

I'm totally clueless when it comes to the masking tool.  Any suggestions on how to learn how to use it other than me searching "photoshop masking tool tutorials."  Is there a specific  type of masking tutorial that I should be looking for or, is it just best to start from the beginning?

Its very simple...this may help you as you can see I have made some wings and, I am using the layer mask to tidy them up.

Basically, as previously mentioned the layer mask helps you to alter the appearance of an image without destructing it.
The layer mask is useful for removing any unwanted parts of an image. You will need to be continually altering the size and softness/hardness of your brush to access various areas of your image. By selecting WHITE from your foreground/background palette you will be able to restore parts of your image which have been accidently covered by your BLACK brush.

Lunarcore do a nice little explantory tutorial which will help you.

 Another viable option would be to just mask off the areas you want to work on and use the Liquify tool to push and pull bits of the edges.  --- Before you do your Blurry-layer-post-work though, so you can have that effect for the new edges rather than pushing and pulling the effect around like I did. (which makes it look a little wonky)