Sometimes it's not what you put in your rentals, it's WHO you put in your rentals.solidreturns, do you remember what millimeter thickness you bought?

It was 6mm (millimeters).

I stay away from the diamond-coated variants of these blades because I've chipped the edges of tile with them.After you dig the top layer of grout out of your installation with this tool (no more than two or three millimeters), you go over the same grout lines again with a thin coating of pre-mixed grout.

These shrink perhaps a few millimeters per decade, but if you add up enough decades, that will cause the floors to sag and tilt. 

In other words if you hesitate or give 1 millimeter they will take advantage of you every time.