This isn't exactly a DIY ask, as I won't be doing very much of this myself, but I wonder if anyone could help me assess the cost of my plan if I choose to do it.

I'm British so I'm pricing this in pounds. I'm trying to rearrange this badly thought out house in a cost effective way, and reclaim a lot of that wasted hallway space.

Do you think ~£60,000 is a realistic price for this work? I'd like to think I'm overestimating.

People keep telling me bathrooms cost a lot more than I think, but I'm struggling to see how, maybe I'm ignorant.