It depends on your ability. If it is a full tile that is easily accessible you can most likely do it yourself. Start by using a grout-scraping tool to remove the grout. Then chisel away the tile and thinset making sure not to disturb the surrounding tiles. Finally set the new tile back in place with thinset, wait 24 hours, then grout in.
Michael Prachniak - Expert Tile and Stone Consultant and Writer, Owner - TileProductions.com
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