Mr Punter

They are having a panelised system so N/A. Paying part by credit card could give some added protection.

I like the guaranteed airtightness results you get with the likes of MBC and the whole superstructure being the responsibility of one entity. If something does not work out on site or BC pull you up, you know who needs to get it sorted.

I think that is a large risk. It would be far safer if you got a firm to design, manufacture, deliver and erect.

Red would be foul, blue surface. You would need to divert them if they are near the proposed building. Don't assume they are near where the drawings indicate. They may be fairly deep.

Not the best but it will be fine. Are the bricks Forum Smoked Branco? The mortar goes well with them.

Sorry but 25mm conduit for a 25m run is a no-no. Can you get a Cobra type duct rod?

Swap the dishwasher and the drawer unit.

Use resilient bar at 400ctrs instead of batten if there is habitable space above.

Bear in mind that the planners often want you to be able to go in and out in a forward gear, so you will need space on site for turning. You may do well to extend the driveway / parking areas.

Is the plan to make it all line up left to right and along the length?

I have seen it done in hot bitumen. It looks quite an intimidating project.

You don't need to do anything. The only issue may be if you have parked cars in the road and the council become involved.

It may be better to have the rafter insulation extending full length of the rafters instead of insulating the dwarf walls and part of the ceilings below. 30mm of insulation under the rafters is also good and will help eliminate any condensation / damp potential.

If your written deadline has expired I suggest you issue proceedings for recovery of the £3,000 plus court fees. You can do this online, although it is a bit tedious. https://www.gov.uk/make-court-claim-for-money/make-claim

The topo looks OK. What is wrong with it? It looks like the site setout was wrong.