Active job

Shower re-tile/re-grout

My partner and i bought a house 3 months ago and we have noticed some wear and tear in the shower. The bathroom looks reasonably new but we aren't actually sure how long ago it was renovated. It's a tub-shower with white tiled walls, on the two 'wet' walls there are a few cracks in the grout and a lot of dark discolouration which i assume is mould. One or two if the tiles even move when touched, which is why we are concerned that there could be water leaking through the tiles. The back wall is 1750 x 1220 mm (just up to where the tiles change from white to black) and the wall with the shower head is 680 x 1220 mm We are interested in seeing some pricing to retile these two walls, or just repair the grout if that's all that is required.