Jo there is a Flying instructors forum on here a bit further down and this has been discussed before . But with regards to pay it can be anything from the square root of sweet FA to about 40 grand . Soem schools pay small retainers and by the flying hour others pay by hour only and some are salaried . Most PPL instructors are on between 10 and 15 grand PA tops , although some may be on more . If you are fully spammed up and can teach CPL/IR MCC etc then you can get quite an nice salary from the big schools .
I will be corrected if Im wrong but retirement for commercials is 60 for single crew and 65 for multi crew I think this is a recent change too