Referring to a member as 'ignorant or ignorance' is an insult, if any of used those words at you, the report button would be hot.
We know you know it all, but please give it a rest ...................
When I buy tiles, there is always some left over from the box, which I keep in case of a prob, other than that I don't buy extra, though I do keep all off cuts of everything, plus screws, nuts and bolts, you name it, that's a lifelong habit.. .....