Hello there,I am an Architectural Visualization Artist and recently decided to give blender another shot,
The issue I face is that ,in Interactive Viewport the render looks very great but in the Final Render it looks awful,pixelated textures and displacement.Rendering at 1080p.
The only real difference is lack of geometry on the final render, I am almost positive you must have your viewport subdivision levels high, and your render subdivision low; as in the screenshot below.
Crank your render subdivisions up and it should fix it.
The only other cause I can think of, is if you have a low poly version of the wall you hid in the viewport, but didnt hide in the render. That would look like this, note the closed eye indicating hidden, but the camera icon, which is render view, is not greyed out, so it will render.
I guess you could also have this problem if you put a decimate modifier on the wall, and turned off the viewport display but left the render disply on.
..
, it’s even more a guessing game for the community than for you 
