At the domestic level I doubt it.
Integrating all those together, especially when 3 of them are large variables, is not going to be easy.
A large battery storage will be needed as a buffer, but the that is not cheap.
I am pretty sure they are all the same, polyurethane based systems.
Performance wise there is probably no difference.
Pick the cheapest.
Can you post up a picture of the GRP and the stained ceiling.
If the GRP is in good condition i.e. not leaking, then the problem may be condensation, and that is a different problem.
I think the use of straw bails is a terrible idea.
But the fact that you are giving it a go is brilliant.
The foundation side of it is interesting as well, you will get a good 'feel' for what is happening under the ground.
The roof will be the best bit.
I would knock up some simple beams from OSB or ply. But I would say that as I knocked one up just for a laugh one afternoon, just to see what would happen.
Get one of these:
https://www.machinemart.co.uk/p/clarke-con14-contractor-355mm-2400w-abrasive-c/
And one of these:
https://www.machinemart.co.uk/p/pro-90-mig-welder/
2 of these:
https://www.machinemart.co.uk/p/cl-cvr5rb-bench-vice/
Make your own.
As ice gets colder, it conducts better, and absorbs less energy to.
A garden ornament at -100°C should start to freeze out atmospheric CO2.
Imaging collecting that is garden bags and taking it to the dump on a Sunday morning.
I just looked up the thermal conductivity of ice at -30°C.
2.5 W/m.K.
So can still get a fair bit of energy though it as the face frosting would not be too thick most of the time.
Have you not just described a split A2WHP system, but with a smaller external fan unit.
I think the problem is physics, you would need a large airflow externally, which may generate more noise, and not be very efficient.