It seems so many years ago:
Our math master, Peter Corlett had a Chipmunk, he used to let us take it home on Sundays, there were seven or eight pilots in the school. That was in Oxford, flew from Kidlington. Oh yes, we used to contribute 3.00 GBP per hour!
I was also able to 'Borrow' the plane and hire an instructor to get my conversion off theColt, helped a bit I had done 14 hours with the UAS at Summer camps.
Don't know about the regs today but is there anything to stop a person borrowing a privately owned plane and hiring an instructor? Seems to me if you make no more of a contribution than actual immediate running costs (ie, not 'hiring') and students might have to arrange insurance extension........
I'd echo the sentiment, build something simple, preferably aluminium and reasonably robust.
Suppose you are not at that establishment on the Banbury Road?