Just a thought, but would it be worth asking around and advertising to see whether anyone in the area would be interested in sharing something like a Jodel D112? I've heard that the D112 is the ideal group aircraft - cheap to buy, cheap to run and lovely to fly. An example could be a group near Bath where they share a D112 between six people, and each pay £45 a month and £10 per dry hour.
Seems like very good value to me, considering that you can pick up a recently rebuilt one with less that 300 on the engine for £10k