Unhappy with tiling in Extension

Recently employed a builder to build a small extension and renovation in my house.
I was happy with the build, on time and on cost, however the builder contracted out the tiling to someone else.
Large floor area, tiles cost me €2,000, long wood effect tiles.

The tiling appears poor in my opinion

-numerous small holes in the grout, ok can be fixed.
-several of the tiles have a hollow sound when knocked,
-various tiles appear uneven, not flush with one another, you can feel the join when you walk across the floor in socks.

I haven't paid the builder in full, until snagging list is completed, in fairness to the builder, apart from the tiles, they can be sorted.

Meeting with the builder and tiler tomorrow, any advice?

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the_pen_turner

long tiles can be a pain to lay.
i layed some in our sitting room at home. look lovely but a bloody nuisance.
some of the tiles were really badly bend

i put 2 face to face to chack them and could put 2 2mm (4mm) spacers between them