Interesting question Tiggermoth. I'm not sure about finding an engineer, although I think any sound maintenance organisation could help.
Would you always go for an inspection on joining a group? If you were thinking about buying into say an old 150 with comprehensive maintenance records, a recent bare metal respray and a group that has clearly taken every step to care for the aircraft? Would an inspection be economically viable if the share is less than say £2,000?
All views welcome.
HH