Roundtuit

For good measure, I'd also cut the concrete/paving slabs back by 6 inches adjacent to the brickwork and fill with gravel to reduce rain splash.

My advice is to take on board whatever @craig suggests. Unless your agreement with the installer included improving building fabric to mitigate existing cold-bridging, then you only have some minor snagging issues that you could probably have resolved yourself with some expanding foam and sealant in the time taken to craft your comprehensive and eloquent posts!

I was reluctant to pay someone to do something I could do myself; did one ceiling with a roller and realised how long it was going to take to paint the whole house... Painters are not that expensive and come with all the kit 😉

The old classic: lt is easy; it's like riding a bike, except the bike is on fire, you're on fire, and everything is on fire because you're in hell...

Less plot and professional fees etc...? Any indication of plot costs in your catchment area would be helpful, and how hands-on you plan to be?

Is the 3 inches the full depth of the rafter? If so, I'd be cautious of hanging any additional weight off 75mm rafters, and be looking for a solution that added strength not just extra load I think.

Surely. Unless you're building it big enough for the sheep as well.

Hire a couple of hand pallet trucks and use one each end maybe? Just remember to build it on blocks so you can get the trucks under easily.

I have a separate thermostat for upstairs. What have you got upstairs that should be 'calling for heat'? TRVs?

Probably just tape the small bits. For anything bigger, I believe the recommended fix is to slit the membrane horizontally above the damage, slide a patch up and in so that the top of the patch is on the inside of the membrane and the bottom of the patch is on the outside to shed moisture, and then tape in place.

Once it starts, its like an expensive roller coaster ride that you can't get off until it's liveable. Pace yourself, improvise, adapt and overcome, and remember it will be worth it in the end!

Wheelbarrow and shovel for me, or bucket and trowel for really small mixes, but that amount doesn't go very far.

I've got a 10ft container to pretty-up at some point. I think I'd drill the holes first and screw from the inside into the timber, or weld a few angle brackets on to avoid holes in the skin.

Probably not a massive oversight then; more a difference of requirements. Night latches usually require additional locks on the door for security so are superfluous with multi-point locking systems. I can't really see an overwhelming argument for having one tbh, but if you can, probably best to replace the door with another timber one and fit one.

I'm guessing you're used to a nightlatch type lock?