Here's a new concept. Why not demand a basic and a flight pay after you have flown eg. the first 20 / 30 hours (depending on the basic).
If I am being paid and the weather is poor, I don't mind painting the kitchen and toilets, just give me a fair deal that I can live on.
I have seen some schools that really take the pi##, charge the students top money for very poor aircraft, then have the face to pay a joke of a days pay.
I refused to take the offer when I saw the conditions, needless to say.