Hello all-- Long time lurker who has had many, many questions answered just by perusing these threads. Long story short-- those pink pavers where the foundation of an old aluminium shed that the house's previous owner had and I recently removed. Around the pavers is concrete (the whole back yard is concrete) and to the left and right to the space are retaining walls. Here are my dilemmas: I want either pour concrete where the pavers are now or build a small deck. Either way, I have that space where the wall on the right side ends (originally, the shed acted as what kept the soil from shifting) and the unevenness of my yard and the yard of the neighbor behind me (you can notice that there is exposed soil under the fence) So as to my actual questions-- if I were to continue the retaining wall on the right until it 'connected' to the fuller wall on the right, would that sufficiently keep soil from shifting from my neighbors property? If I were to do that, would pouring concrete add more reinforcement? If I were to pour concrete, would I need to stake things out on only the left and top portion (along the new retaining wall)? I'm at a bit of a loss as to how to put concrete in that portion. I'm a bit perplexed as to how to proceed-- I have a feeling I am making this far more complicated in my mind that it actually is, but I figured a few opinions as to what to do would be greatly appreciated.