My apologies if this is addressed somewhere else but I am just looking for advice on what fees specifically to pay and has anyone had experience crossing back and forth from the US while their application was being processed? Clearly I pay the sponsorship application fee(me) and I believe principal application fee(my wife) and there was also a permanent residency right fee. Do I pay that now or later. I am a Canadian citizen and my wife is a US citizen (formerly PR of Canada but residency requirements have caused this to lapse). If there is a forum that I can join could you please direct me to it? Thanks.