Question for those with the stone fireplace

This week (yesterday) they installed the stone facade on the fireplace.  I think they did a pretty good job on the stone but the mortar is pretty bad.  The sides are dark/messy and there are some serious stains on the pretty hearth stone.  Does anyone with the stone fireplace have any staining issues on their hearth, as shown below???   How do they finish the edges?

I wanted to catch them before they installed the mantle because I wanted it lower (or not at all) to be able to mount the TV a little lower but they had it done too quickly.  

I  was also disappointed to see there wasn't any stone leftover (and there's no dumpster in our yard anymore so no diving).  I guess I'll need to ask PM to get a couple of extra pieces.  I would like the extras to use to cover the TV hookup hole if I ever want to take the TV down in the future.