You will no doubt be one of many putting in a price to do the work and it will normally be based on the same tile or one of equal value.
You should find out the tile,the cost,the availability and word your estimate accordingly - like for like/ materials of equal value.
Clearly word exactly what your estimate covers from strip out to clearing the site via a skip etc.
You must make your payment terms a top priority and state exactly at what stage you require your money ie. materials deposit - materials on site, final payment -on day/7days/etc of completion.
If you get the job find out at this stage who you are working for - is it the customer or insurance co. in other words who is going to pay you! If its the customer they will need to have the funds available on completion and they will make their claim via your invoice for the work completed. If its the insurance co. you need to have a contact with the assessor to confirm your payment details - before you undertake the work.
If you are happy to do the work and wait 30/60/90 days that is of course your choice
Good luck with the estimate
Timeless John.