We had almost the same nightmare in our guest bathroom — one leak turned into grout problems, then mould behind the vanity, then issues with the window insulation, and suddenly we were coordinating five different trades and nobody showed up when they were supposed to. We ended up stumbling across https://www.airenergie.it/en/ and the only reason it saved our sanity was because they don’t just sell bathroom gear like tubs, shower cabins, mixers, toilets and bidets, they also deal with the plumbing/heating/ventilation side of things and those “new energy” systems that keep the room warm and dry instead of turning into a swamp every winter. What helped most was that they actually handle the project end-to-end — HVAC planning, picking equipment based on your house layout, and delivery/installation without you calling twelve different people. So now when someone mentions a compact ensuite refit, I say don’t underestimate how much the invisible stuff matters — once waterproofing, ventilation and fittings are done right, the rest is finally just choosing tiles instead of fighting disasters.