@YTY2024 thank you for the responses to my questions -- I think I understand the situation a little better.
Your Q1
For exchange rate CA$ to US$, you have a few choices --- monthly average, semi-annual average or annual average -- these are all published by US treasury or wall street journal or Yahoo finance etc. A point you have to keep in mind -- you must use the same source for every transaction and keep good records as to how you converted CA$ to US$.
Your Q 2
Generally Foreign Tax Credit works pretty much on reciprocal basis -- thus if you choose to get foreign tax credit in the USA -- then the amount of credit allowable for the tax year will be lesser of US tax liability or actual taxes paid to foreign taxing authority. Canada will do the same if you choose to use foreign tax credit in Canada. You can get credit from ONLY one country.
I general , I would strongly recommend that you try both MFJ and MFS ( for US purposes along with Canadian taxes) to see the fuller picture. Also note that the many states do NOT recognize tax treaties between US and another foreign country. However, many do allow Federal as MFJ and State as MFS because only one is a resident. )
Another point to consider is to declare the husband with a different tax home . This will allows use of excluding foreign earned income from US taxes while filing MFJ
I am assuming here that we are talking about tax filing for the tax year 2024 ( f to be filed in April 2025 )
I understand the tax treaty question. However, do want to add that if you have questions/ situation s not of interest to the general poster, you can always PM me -- this is not visible to the general board ( with the proviso that you post NO Personally Identifiable Information ).
Is there more I can do for you ?
pk
