Hi. That depends on too many factors to speculate here. Have a contractor or two come in and give you a quote. Good luck.
, Hi MC,
It will cost you the price of the extra new pipework the time it takes to do the job.
I'd say anywhere from 2000.00 to 5000.00 depending on far you need to change extend the sewage lines,water lines,then jack hammering up floor and repouring concrete. we had bathtub drain leak in concrete slab foundation and it was over 2000.00 to fix & we did not relocate anything
Don't do it if you do not need to!
Depends on what you are trying to achieve. I moved a toilet diagonally across a bathroom by simply routing the soil pipe around the wall. The exit for the pan came straight out of the back, approx. 6" off the floor. The soil pipe (4" dia) ran across the front wall, dropping to approx. 3" and then across the side wall, terminating in a right angle down into the original soil pipe. The length of the bath covers the pipe along the side wall and partly across the front, the rest is covered by an under sink vanity unit and some painted MDF. The pipe drops a total of 6" along 12' with three right angle bends, it's been in place about 10 years with no problems whatsoever.
I notice your soil/drain arrangements differ to ours in that you seem to have a rule about installing yards of pipework on every sink, bath, toilet etc purely to vent fumes whereas we (in the UK) rely on the U bend of the toilet and similar on pipework from sinks & baths - And I have to say that I've never noticed any nasty pong.