@john clark I have just bought a walk in shower tray with fixed screen with black profile and support arm for £365 from showertraysuk if you are looking for that rather than over shower bath. Like Katie I got my shower (£160) and exposed trap (£45) for the basin from Victoria Plumb, pop up waste off soak.com (£12.99) taps very similar to Katie but with a rounded spout again off ebay (£65) I've not yet fitted my bathroom but I hope it looks as good as yours Katie!!

Have a look at a company called sits, loss of configurations available. I'm not Sure where you're based buy they have a show room within redbrick mill in Leeds and I'm sure they'd have others.

I know! We’re exploring options and are unsure on the best most cost effective solution. We’ve considered squeezing a shower into the downstairs WC, could be done but tight. We have ruled out an extension as the house already requires extensive updating and due to its age we know we will need budget set aside to account for the unknowns! As for extending WC into dining room we hadn’t thought of that, but we have a plan to move an external door to that area so that wouldn’t really be an option either. So difficult!

Yes, prices are kinda crazy at the moment. It will depend on if you need to remove the floor of the conservatory and dig out new foundations, or whether you just need to put a proper roof on it, bring the floor up to the same internal level, insulate more and install new patio doors/windows. Looks like the sides are already solid walls? You should ask builder how much it would cost to take out all the walls and put in steels - that might convince you wife to leave the front room separate! And making part of the current kitchen into utility/pantry means that most of the wall between kitchen and dining can stay too - cheaper than putting in new steels and you also get a really useful space. Water is already closeby so hopefully it shouldn't be a huge issue to move the toilet and washing machine over to that space and there's a few different ways to configure that space.