I was first thinking the color faded. Some jobs done poorly I have seen blue with yellow neutrals. I guessing it's a foreign labor not knowing the rules.
Putting in arkfaults is a bit much for just selling a condo IMO.
Does it meet code standards when it was built or last remodeled?
Just cover the basics like having GFI's, box covers, trim plates, no problems in the panel, and correct wiering on outlets. That is all the home inspectors will look for.
I like to have everything fine when I sell but I believe the home inspector report has become a tool to get the buyers credit. Does not matter so much how good things are they will still try and say something is wrong. Many times the home inspectors are incorect.
Let the inspectors find your other problems and fix it then. A yellow neutral is incorect and a sign of a poor job done. It is not a make or break deal on real estate.