I always thought it would be a good fall back if you lost your medical or licence.
Advertise course and run evening class at local community school or village hall that could be rented. You would probably earn more than instructing at PPL level.No flying school to run. No responsibility for sending students solo or wondering what a renter is going to do.
I see R/T examiners don't seem to do to badly from the charges i have seen for some ground and practical tests. (My months wage in a day with four candidates. I would have to do 5 skill tests to earn the same amount of money over 3-4 days).