The reliable way to hire a tradesperson

I’m so lost with what to do here. We’ve recently gutted out our avocado bathroom suite and the wall on the left had tiles slowly coming away from the wall with one tile popping off completely and this is the condition of the wall. We’ve discovered a section that sits just above the bath is grey and crumbled a little. There was water damage that affected the floorboards that we discovered after moving in. We’ve now had our new bath put back in and was advised to just pva over the walls and put new tiles on the wall from the bath upwards. Is this really all that needs to be done or am I right in having doubt? I actually wanted to sort the wall out before the bath went back in. I’ve seen tile backer insulated board and wondered if we can use that or can we seal the walls before tiling? The left wall is plasterboard and the top end of bath is cement/plaster wall. Appreciate any advice!

Hi all, I’ve recently stripped out a concrete pad and want to install a patio. When digging out I found the foundation for my house so I’ve installed the acos in top of the foundation and my new finish level is 80MM above previous finish level and 70mm below DPC. Looking at the photos will this be acceptable? If not would installing additional drainage directly next to the house in the gaps would this fix the issue? Final option is digging out all the type one and reducing existing levels remove the acos and have the fall away from the house. (Probably would have been best option but I’m pretty invested in this setup right now). Thanks

My electric shower keeps tripping, is it best to replace the full unit?