It's a very gray line and you really need local RE legal advice here.

Firstly, the basement walls' color was black / dark gray and we discussed on the phone that they will use some neutral color for it.

I am currently looking at properties in Thurston County, Lewis County, Pierce County, Mason County, and Grays Harbor County.

Using only gray water, it doesn't have the macerator.

That really helps because it leads to some other gray areas I had about the process. 

The rock is a black and dark gray color, not appealing.

But that seemed like a huge gray area as well, which I don't know if I liked.

That's a gray area but it's not our job to be their conscious.

The gray area might be whether they will tow a car if there is no sign posted that says "no parking violators will be towed at their own expense".

https://www.homedepot.com/p/Home-Decorators-Collection-Stony-Oak-Grey-6-in-x-36-in-Luxury-Vinyl-Plank-20-34-sq-ft-case-60198/207047495It looks really great with repose gray walls and bright white trim.