IR exams....
Here are the IR exam requirements - if you let the 36 months pass, you'll have to take these again - no joking - it's all in LASORS ! The only way you can get out of it cheaply is to do a plank single IR, thus validating your exams permanently. You can then do your heli IR when you can afford it at a later date. This is the lesser of two evils i'm afraid.
Air Law
Ops
AGK
Perfromance&Planning
HP
Met
Gen Nav
IFR comms
TFS