Inquire about their cleaning approaches: hot water extraction for carpets
https://wiki-byte.win/index.php/Tile_and_Carpet_Cleaning_Services_Checklist:_From_Grout_Cleaning_to_Deep_Steam_in_St_George_58346
Inquire about their cleaning techniques: warm water extraction for carpets and correct grout-safe methods for tile to prevent damage and residue.