I charge £27.50 inc. cement based adhesives, grout and trims (plastic, metal charged extra as they are a PITA to fit) This is for std format tiles.
If tiles over 600mm then £35p/m2 as they can use a lot more adhesive and take longer to work unless the walls are super flat.
Stone work, i.e. Slate, Trav, Marble etc. then £40p/m2 to allow for the extra wet cutting and sealing.
This in in Leicestershire. I’ve been tiling for 20 years so think I’ve just about got a grip on pricing.
The Company I sometimes sub too somehow get away with charging £45p/m2 for ceramic/porcs, a plumber I know who does a bit of tiling and ‘not very good’ by his own admission charges £35 because he’s slow?!? and gets work. I’ve also lost jobs for people charging £15p/m2 which in my opinion is not enough to not be cutting corners. I’d always go with recommendation and reviews rather than ultimate price.