JJ
IUI is definitely a simplier process, it's not really the $$, but the process itself.
ER will mean that u will need to undergo day surgery and be knocked out at the operation theatre. then u'll feel super painful if u retrieved many eggs, because of the poking into the ovaries by your gynae to harvest the eggs..
the ET will be like IUI, where the doc will insert the embryo into ur uterus,
but the thing with IVF is it's a confirmed pregnany if your embryo is viable and implants onto u. whereas for IUI, u stll got to have your egg burst out of the follicles (if there's eggs, cos not all follicles contain eggs), and then meet the washed sperm, and travel down to ur uterus and get implanted.. it's as if u're having a natural cycle, with the help of the sperm being nearer to the eggs.
hope this helps