[lightbritefight]

I like your plan, but I think you need a steady subscription cost. This subscription has the two fold advantage of giving the space a predictable income, and it makes the spaces participants less likely to engage in "not my problem" usage of the space itself, ala tragedy of the commons.

A hybrid system like what zipcar uses might work well. A small yearly membership rate (roughly £50/year) + reduced £15/day usage rate. Best of both worlds.