Advice..

Okay ladies, I was in the process of completing my first IUI, however wasn't able to go through to the end because the 7.5ml Letrozol I was taking did not work on making me ovulate. I've had the same issue with Clomid as well and have tried these medications multiple times. My Dr is now wanting to discuss the options of IUI with injectable or IVF since the highest dosage of Letrozole and Clomid have failed numerous times. I struggle with PCOS and with planning a wedding, a moving into a house money is very tight for us. My fear is spending the money and not having it work for either. Has this happened to anyone before? who has does IUI with injectable and had success their first try? My sister in law has agreed to be a surrogate for free if needed and I'm almost thinking that would be the best fit if we have to do IVF. I say this because I would be twice as devastated to go through IVF and miscarry because of my high blood sugar. She has already had two healthy babies and have had no troubles getting pregnant or miscarring. I mean, i would love to be the person to carry my child, but if i cant id rather it be her. What are your thoughts on this?