The red clay under most Union County yards is tough to build on. It holds water after a storm, swells, then shrinks and cracks when it dries out. Set pavers or wall block directly on it and they'll move with it.
A patio that lasts starts with excavation. The clay comes out, a layer of crushed gravel goes in and gets compacted in lifts, and a thin bedding layer goes on top before the pavers are set. The whole surface is pitched slightly so rain runs away from the house. Skip any of those steps and you'll see low spots and loose pavers within a few seasons.
Retaining walls have a different enemy: water pressure. When clay behind a wall gets saturated, it pushes. That's why a proper wall has a compacted base, clean drainage stone behind the block, and a perforated pipe to carry water out. Walls that lean almost always skipped the drainage.
Before you hire anyone for hardscape, ask how deep they'll excavate, what base material they use, and how they're handling drainage. A good contractor answers those questions specifically, and puts the answers in the written estimate.