What kind of flooring? If it is SPC, appearance wise it would look nicer if flooring is done before your built-in wardrobe. However, based on what I learned from a flooring shop, it is actually better to do the built-in wardrobe first. The reason is that SPC relies on the skirting to leave gap for expansion. If your built-in wardrobe sits on top of the SPC, the floor may not be able to expand properly and issues may arise.

Does anyone have experience with hacking your tile skirting in order to do SPC flooring? Currently I am considering doing SPC flooring but I will need to remove the existing tile skirting, level it with the wall and paint it before SPC can be done. I am afraid the color will look different from the existing wall paint even though it is white.