So, I just finished this course, and here is my first view of the final render.

Here's another view:

I wanted it to be very minimalist and bright, so I used a concrete white texture on the wall and I kept the baseboard really simple.

I searched websites for interesting and more realistic textures, my recommendations are:

Flying Architecture - They have a lot of realistic textures and materials, they're FREE and you can also download 3D models, which I think are very helpful to learn how to do new stuff.

Greyscale Gorilla - They have texture and lights kits, and a lot of tutorials. The kits are available for sale, and the tutorials are free.

DeviantArt - You can find textures, materials, and models just a few searches away.

Behance - Lots of inspiration to offer, and many different applications to 3D Modeling.

:)