As someone who worked a lot on construction shops, it's usually the later, but you don't do like Linus where he puts things there, you let the area open and without anything on it until is done.
A bit of autistic construction rambling about tiles tiles, you should never buy X amount now and extra Y amount next month. You buy everything at once with a few extra boxes. Tiles manufacturers guarantee equal size, color and thickness by batch, so if you buy new tiles after a few months, it will look the same by itself but when you set them besides the others, you will notice the difference in size, thickness and color. That variation is not that big, less than 2% but it's noticiable when you put one batch besides other