You still need the schedule, because the builder does not itemise everything so there is still some estimation required of what individual items (eg an oven) cost, even though you know the total amount.
Also, it would be a lot of paperwork and headache for you to calculate the depreciation each year without a schedule. If you have an accountant, they would no doubt charge you extra to calculate this anyway, so you might not save any money by not getting one.