For those considering a career as a flying instructor here's a general view of PPL instructor earnings based on around 600 hours a year:
PPL on conventional Fixed Wing: £12k pa
PPL Microlight 3 axis Fixed Wing: £36k pa
Cost to gain FI(R) on conventional FW - (CPL + FI rating): +/- £24k
Cost to gain FI(R) on FW 3 axis Microlight - PPL + FI rating): +/- £12k
Best return on investment has to be as Microlight Instructor