Grout issues in new bathroom
This community has been amazing for questions I've had in other parts of the house: please, please go to town on the latest.
We have had a new bathroom finished for several months, and our contractor, who is a family friend/business associate, said that he would come back and fix anything that we did not like, after we had lived with it for a while. Now I am seeing holes (well bigger than pinholes) in the grout on the walls and cracked grout where he built us a tile shelf. That's just the walls. The floor is worse. A bunch of the grout has come loose, and I have hollow spots where I can see through, possibly to the pan beneath? I think I can feel the tile squishing/moving beneath my feet as well.
So here are the questions: Do I ask this guy who clearly made a couple of mistakes somewhere to come back and finish the work? Can this be regrouted and fixed if it's this bad? These are the noises that this fellow has been making. However, it looks to this inexperienced eye like a total redo may be needed on the floor.
I know that sight unseen, it's hard to know what to advise. But what are the questions I should ask to get this guy to do the right thing, or to better evaluate the next person who comes to fix it?
ps -- the time allows in the next couple, I will send a picture of the floor.