Mr Punter

I like the projecting window reveal at the back. I will be interested to see the completed elevation. Paving looks a tad uneven!

If you can, transfer the survey markings to just outside the building footprint so you can easily run a string line down the centre of the trenches and re-mark.

Email and WhatsApp seem popular. I prefer email as it is much easier to sort, forward etc. WhatsApp good for sending site photos. The desktop version is useful too. I don't think you will find your ideal system. Try to resist frequent contacts as they can get ignored if it is several times a day. Can you do a meeting / phone call maybe twice a week and send a note of what was discussed / agreed?

They can often be at 4m centres.

Is it piling mats - concrete blinding to stabilise a piling rig?

Choose one and use it all over. Far easier and quicker.

Put the hob on an outside wall run and duct straight through the wall. I have an externally mounted extract so I can get lots of extraction of cooking smells and smoke with very little noise. It is what nearly all commercial kitchens have. Not so important if all you do is steam a few veg and order in takeaways.

I don't think crack stitching will work with random stone. It needs horizontal mortar beds. You are braver than me to even look at this property.

Rip out all the mouldy plasterboard and timber. You will need to move the wardrobes to get this done. Can you claim on insurance?

If there is space, a lorry mounted boom pump is a real time saver. Hire a rotating laser level. You will still need a mate to help. The pumps make a fair mess when they clean out. You can end up with a fair amount of concrete and washout, so plan somewhere for it to go.

Make sure your access is OK for the truck. Could be 3 x 8m3 loads. 32 tonne each. Hopefully the lorry can back up near the trench, maybe either end. Ideally you want trench inspection 1st thing, then concrete early. It can be annoying hanging around then having to work late because you are not a priority customer.

We had some old railway track on a site. Very difficult to cut with a petrol disc cutter.

If you have got the next stages planned in, with contractors lined up, and building regs / warranty people giving the OK to your proposals, you could go ahead. It is not monsoon. It has rained in this country before. You are not made of sugar.

Yes you can tile these. I am not sure why they would need to "breathe".

Normally you will leave the battens short of the window opening so the air can flow round. Like this: