Installing tile, need input

Removed preengineered wood floors from laundry room due to a leak that causes the floors to warp from destroying the wood glue underneath. We want to put porcelain tile as replacement and it’s just cement slab beneath the old flooring. Anything I should keep in mind so my contractor does the job right when installing the tiles?

Removed preengineered wood floors from laundry room due to a leak that causes the floors to warp from destroying the wood glue underneath. We want to put porcelain tile as replacement and it’s just cement slab beneath the old flooring. Anything I should keep in mind so my contractor does the job right when installing the tiles?