for above job id be bout the same maybes a wee bit more for the levelling and sealing, so imho no i dont think your expensive but you need to try and justify your rates, explain whats needed and why it costs so much, on the other hand you could use thick bed addy and levl from that.
just started on monday a 101m2 slate floor, sheera modular slate
went in right away at 40 a m2 plus materials, nice and easy 5 grand for that, dont do day rates, i turn up at 8 and if im finished for the day by 12 then am finished, done day rate once and punter was clock watching me all day
also in same house 2 x 5m2 splashys with 2 sockets each, fine i said £15 per linear foot plus materials, she is very happy with her floor so far and didnt even blink, think that equates to 90 a metre lol
WHERES ME MASK AND GUN
andy