My dream (besides helping my DDs out and buying my villa in Tuscany!) would be to set up a charity to buy small studio flats for single or couples who are homeless, as this is the demographic which falls most often through the net!
Rents would be set very low,and benefits would be accepted,each tenant would have the option of a support worker funded by the charity, to help them settle in to stable accommodation, sort out benefits, get furniture, arrange bill payments etc. and help with accessing debt advice (if needed)
Having worked with very disadvantaged clients over many years in my job with a legal advice charity, I found that this is the group which usually draws the short straw with getting support and a leg up, especially the young homeless people.