Thanks for the advice. Decided to take the travertine back and used ceramic imitations instead. Saved alot, looks pretty good and the tiling job went well.
I'm foolishly planning to self install 60 by 40 mm travertine tiles on wall as a bath surround. The existing tiles are sound but not too flat. I think my two options are hacking off the tiles and replastering or dryline with backerboard/aquapanel or ply. Any advice would be appreciated. Space is a b...