Sorry to hear about those living on very tight funds. I was like that in my 20s and I remember the frustration of having to choose between having trousers long enough to reach my feet, or having food, or having a mobile phone that would enable me to make friends. You're quite right to stay ruthlessly away from debt. Hang in there.
Girlie thanks for the ideas, especially on cooking. He's gradually outgrowing some food issues, and learning to identify and work with the ones that matter himself. Wheat intolerance is not such a huge problem here as a lot of people are wheat intolerant, and there are tons of cafes around here that serve non-wheat food.
One of the big plusses is that coming home for lunch is making him much more confident about being in school, which makes life so much easier, so I think I will keep the home lunching. However, home lunching is getting easier and easier as he gets more enthusiastic about going back after lunch. 
I think we may also takes steps towards getting rid our carpets. I gather that dust mites mostly live in carpets, so if we throw away the carpets then we also throw away the dust mites. That would take away a huge part of my workload I think.