Reddit reviews Ardex Feather Finish Grey/Gray/Gris Self-Drying Cement Based Bag 10 Lbs

For photography, why not use a feather coat concrete product on plywood or drywall? It'll look much more like the concrete you Invision. Cement board doesn't have the same look

Ardex- Feather Finish 10 lbs https://www.amazon.com/dp/B004GUAIT8/ref=cm_sw_r_cp_api_rZTrybQ5PA6VA

Do a google search and you'll see the different finishes and what you'll need to do. It is durable. Commonly used to make concrete counters over laminate.

That does suck. Looks like they just skimcoated the floor with some concrete something, probably something not suitable for a surface to be walked on. This is probably an acceptable thing to do on a properly prepared surface that won't get much traffic, especially a small one, but it was irresponsible to do it to a whole house. There's nothing bonding that top layer to what's underneath it and with a layer that thin, it's definitely to going to continue to crack and chip off.

You can patch it if you'd like, and try your best to paint the patch, but that's not a long term solution. You can't stain it because different types of concrete won't match even if you get the same stain. Also, I can't tell from the picture, but properly stained concrete usually has a sealant and a wax on top of that as well.

Looks like the proper thing would be to remove all the flooring and get to your subfloor again. Sometimes you can stain the subfloor itself with proper preparation but there's no way to tell without getting down there. Once you get to a bare floor though, you could have some leveler poured if you need it and then have the entire floor coated with a concrete micro-topping, which will actually bind to the concrete subfloor, be durable enough to walk on and give you a clean surface to stain. Unfortunately, none of this is probably good news.

Edit: This or something very close to it is most likely what's spread over that linoleum. http://www.amazon.com/Ardex-Ardex-Feather-Finish/dp/B004GUAIT8