Extension advice

[Shaun_UK]

Hi all, new member here looking for some initial advice. 

 

I am wanting to extend my property for more space. It's a corner plot, and feels a shame not to make most of the space. 

 

Would like to extend the back, but there is already a lip of an extension covering both properties. 

 

Does this mean future extensions on the back are not really possible? Or possible but very expensive? 

 

Including a photo of the current set up. 

 

If anyone has any advice/tips on possible ways to extend based on the current structure, would love to hear them!