One option many instructors take is to hold off on your IR. You can build time instructing and some schools will give you a staff rate on the IR training.
When I first applied to instruct many school were anti CPL/IR/MCC prefering just a BCPL as they knew you could not apply for airlines and they would have warning of when you were planning to leave.
Also if you have a IR and no job or are a PPL instructor there is no point paying for an IR renewal each year as it is expensive.