is there any software available for designing bathrooms ?

I plan to split ours to create an en-suite for one bedroom but am having
trouble with the design
the room is currently 2500 * 2900 and would be split into...

800 * 2900
1600 *2900
allowing for a 100mm dividing wall

or possibly take a 1200 * 1200 (roughly) block out of a corner to create
an L shaped main bathroom

I've discussed it with the local estate agent and she says it's a good
idea and would definitely add more value than it would cost

any advice would be appreciated

thanks