Apparently the installer came last evening and did some of the corrective work. The dug up a few pieces of tiles that were not level and installed new ones, it does look better than what I first saw yesterday though.
I didn't personally know how much the install was, my folks did though. Initially they were supposed to do all 3 of our bathrooms, but now they are just going to finish the one that was started.
Because we were not satisfy with the work, the installer is now asking $130 for tiling the bathroom and installing a new toilet (I know installing a toilet is very easy, but its my folks house and not my decision
). The bathroom floor is around 25sq. ft, I think it's fair for the work completed.
I'll update tomorrow with the finished results!