you need to be careful when you get these tenders some come from the contractors estimating office ,the estimator gets you to do all the work putting a tender together they then price for the job but rarely come back to you as the quantity surveyor takes over when the contract has been awarded, if the tender is fron the contractors quantity surveyor then its worth putting the hours in pricing it up, most of the tender package is waffle ,look for the m40 pages which cover the wall and floor tiling specification ,put your price together then be clear about what the contractors payment terms and conditons are, if you get the job you will get a chance to sit down with the Q.S at a prelimenary contract meeting where they will ask for a discount at this point you have got room to negotiate as the minutes from the meeting are normally typed up and you both sign the official order for the work ,when asked for a discount it is advisable to agree to 2.5% if its monthly valuation and payment after 30 days,offer more discount for better terms and conditions 5% will normally gain you fortnightly valuations and payments depending on how good a negotiator you are ,
good luck with it
Gary