The build

I did all the re-wiring in the house I live in, all the central heatng plumbing as well as all the kithen and bathroom plumbing. I used youtube and google as my friend!
Gawd knows what will happen when my sons & daughter come to sell the house once I've snuffed it as no certificates! I DID get a heating engineer to fit the gas boiler but I did all the plumbing for it!
Horrible memories of crawling under an 18 inch floor space dragging wires and soldering plumbing joints.

At least yours will be certificated SC, with me it was a case of needs must,as I had very little money or time to get it done!

New build, we have no choice. Otherwise Bob would do all the electrics. He’s doing all the plumbing.  He wouldn’t do the air source as out of his comfort zone and the MVHR needs designing for maximum efficiency , again we’re both fairly clueless on it ( me more than Bob ).

I had an electrician to change the house fuse box last year as part of the new bathroom was fitting a new shower and it should really have a trip switch rather than a wire fuse. I did all the plumbing and wiring for the new shower and the electrician was happy to wire it into the new box. He did test all the circuits into the new box which were lighting , ring mains, cooker, 2 showers and consevatory, 8 circuits in all. The certificate he gave me seems to cover the lot. He supplied the box and the total cost was £735 which I thought was a lot but difficult to get any trades people here and he travelled from Manchester.