People bang on about doing an instructors rating, and how that's the way to do it etc.... but if you take a quick look on the net you'll find they are not cheap too, about £5000, and that's really only to PPL level. That won't cover you for multi-engine and instrument, training. Also if you come out of an integrated course, you may just have 50 hours PIC, and more SPIC. However correct me if I am wrong, but you need 100 PIC for a FI rating, thus more money for hour building. All together an expensive operation and that only covers you to PPL level.
MK