Replacing a level access shower with a new bath (with pics)

Hi all, my first post!

Ok, we have a level access shower in our tiny bathroom (was for disabled access, no longer needed) which is on the ground floor, the floor is solid concrete with the drain hole set in into a sunken area of the floor. We'd like to get rid of this and replace with a short bath tub with shower overhead, can anyone advise the amount of work and complexity of a project like this, ie, moving the drain hole? levelling sunken area? how to get plumbing for hot and cold taps etc. I'm keen on doing the work my self to save on costs. Any advice?

The hardest part will be the waste, so where does the existing shower waste run to?

If you have a soil stack nearby then you can fill in the existing floor waste and run a new one from the height that the bath will dictate.

If the floor isn't flat and level then you'll probably need to re-screed at least part of it.

Running the supplies is relatively easy. For example, is there a basin in the room?

Not what you want, but you have all the 'foundations' in place to create a new swanky wet room. Others would dream of having a flat floor access that you have got
Put some decent tiles in, new thermo shower and a fixed glass door/wall, job done.