I personally like the Turbo Hybrid better but the SX12 works too.
Things you'll need:
Blue swivel grout brush
A small hand grout brush, real stiff.
Pump up sprayer
Blue masking tape and this stuff..
http://www.pro-tect.com/PRO-TECT-carpet ... -roll.html ( tell them to cut the roll in half. Use it to protect carpet that sits next to tile)
A 175 rotary or OP machine for scrubbing and sealer removal. Could be done by hand but good lord...
A Glided wand for edging and detail work.
Sealer applicator bottles.
Knee pads.
Alkaline stone and grout cleaner.
Acidic Grout and tile cleaner.
Acrylic floor stripper
Solvent and water based sealers.
Lots and lots of towels/rags.
Things you'll want:
Mini Turbo or Cobra hand tool.
CRB machine for pre scrubbing.
Knee roller cart that Grout Perfect sells.
A class in color sealing.
A class in stone identification.
A class in the proper use of enhancer sealers.
A lot of luck.
And you better be real good at talking your way out of nasty, potentially very expensive situations.